US Moto2 Bike

Finishing the steering stem

2011-11-17T16:54:00.000-05:00

It was way back in July that I turned the blanks for various length steering stems. The various lengths allow me to adjust the amount of dive that happens under braking.

Here's where we left these parts:

Now these parts will be brought to the 4 axis mill and have the pivot holes and clamping faces machined. then i'll switch to another setup and trim and chamfer the ends.

The first step is holding the parts in a 3J collet on one end and with a dead center in the other to ensure the part axis is coincident with the mill 4th axis. That means that the zeroth step is to align the dead center to the 4th axis. I machined a round adapter that helps greatly in this process:

I then remove this mandrel, reinstall the dead center quill and then clamp a part:

To check the alignment I held a .0001" indicator in the mill spindle and rotated the 4th axis. the part was within .0003 TIR, which is an excellent runout for a 2nd operation clamping.

Now that the part is properly clamped and in alignment I can machine the features that mount the upper and lower control arms. the machining is 4 pocketing routines and 2 reamed hole routines ending with the almost complete part:

Repeat this a few times with appropriate modifications for the various lengths and i have a bunch of useable parts:

Now there is a simple cleanup operation to do on each side to round and smooth the ends. The part is held in the 4th axis in a 3J collet with the end just sticking out.

I profile the end, then chamfer it and repeat for both ends top and bottom:

The finished parts are pretty sweet lookin:

Especially when assembled in the spider:

That's one more part to cross of the to-do list. The front end is starting to take shape, i'm only missing the control arms which are next on the list of complex parts to do. I may try to squeeze in a few simple parts before that, let's see what the next week or 2 bring.

That's all for now.

Front end assembly

2011-11-14T21:08:00.000-05:00

Now that the spider machining is done I can bolt the legs on and hope the axle holes line up!

As expected both legs fit properly and the axle is a nice smooth sliding fit through both legs. The assembly looks pretty cool, especially compared to the simple previous design.

Once I finalize the rim/brake rotor combination the radial caliper mounting holes can be machined in their proper places. The calipers are the dual Brembo radial mount big pad CNC versions (with the radial caliper too) which will be total overkill for such a light bike, but we like overkill on the brakes, which should be the bike's strongest point. Why Brembo? They are the best. Period. I got them from Fred Renz at Yoyodyne who has a huge selection of high end parts at good prices. Rims, brakes, bodywork, slipper clutches, etc. No waiting for drop shipping from the manufacturer, he's got it all in stock.

The rotors are Brake Tech Iron Rotors that use a different method than the usual round button to transmit the braking torque from the rotor blade to the carrier. When we were running the Ducati/Rotax single which only had one front disc the buttons on various name brand rotors were constantly being galled and requiring replacement. Once I switched to the Brake Tech rotors all wear was eliminated.

In this photo you can see the flat surfaces that transfer the load. The buttons are merely for axial retention. All the parts are finished to a high level of detail with a nice even anodized finish. The rotors are even cryo treated!

They are definitely a manufacturer I recommend when replacing brake rotors. If you have deeper pockets they also make a ceramic matrix composite rotor that works great on the street. It is super light and great for a track day bike but unfortunately not allowed by most race organizations.

Next post will be the 4th axis work on the steering stem, hopefully in a day or 2.

T-shirt design is in!!

2011-11-07T17:28:00.000-05:00

After starting a donations post for the blog that you can see here I realized that we didn't have any t-shirts available and didn't think people would want a plain fruit of the loom.

My solution was easy, call Sacha Halenda of Form Five and have him whip up something superb. Sacha is responsible for creating both the Cosentino Engineering logo and the 'Cosomoto' name and gear/wing logo, among many others. He has a great talent for creating an identity that is new and unique yet still allow that graphic to evoke the familiar emotions that consumers need to relate to a new entity.

The first shirt design focuses on the V4 engine design and features a large wireframe drawing of the motor on the back side and the text 'crew' on the front with some stylish accents. Although we have not finalized which vendor will print the shirts we will be using shirts that are 100% Made in the USA.

Front:

Back:

The bonus of having one of these shirts is that if you are wearing one at a race event we're at you are welcome to come in our pits, pull up a chair and make yourself at home. Without one of these tees you can come in but you'd better not pull up a chair..... Also, you'd better like Mexican food as we have a rule about not eating anything else for dinner during an event. We have a detailed map of every Mexican restaurant (or taco truck in the case of the Bonneville Salt Flats) within 50 miles of every US racetrack so are never caught unprepared. Cue whatever jokes you can think of about more gas to help the bike go but it works for us!

As we continue with the project and as interest allows I'll have Sacha make more shirt designs relevant to our current state of progress.

If you like the shirts please go over to the donations page and make a contribution. Don't forget to let me know what size to send.

Chris

Machining the front spider

2011-11-07T15:26:00.000-05:00

With momentum still rolling along I started on machining the center spider for the front suspension. This is a multifunctional part that holds the upright legs, defines the steering axis, and connects to the control arms and steering links.

We'll move along the well-rehearsed path of machine fixture, mount part, machine part, reorient, machine part again. The fixture has several dowel pins to register the part in correct alignment before it is clamped down onto the swivel pads that provide proper spacing and restraint.

Here's the part clamped in place:

I then machine the part in 3 steps in this arrangement: the top and 2 sides.

These first 3 operations are all done with simple end mills and drills. When I index the fixture 90 degrees to machine the steering stem bearing seats we will need to use some extended reach tooling.

Here's the 2 flute insert mill used for roughing, the boring bar used for finishing, and the custom long reach retaining ring groove tool made from a slim carbide slitting saw and some precision ground 5/8" diameter shafting.

Here's the finished bore:

And some finished parts:

There are 2 different versions of the part, a tall one that provides much less front end brake dive than telescopic forks and short one that provides closer behavior to teles.

Once I do some deburring and test fitting I'll post some images of the front upright assembly. It will look really cool.

That's all for now.

Na, shafts are boring

2011-10-27T13:12:00.000-04:00

I know the last post said the next one would be doing the oil pump shafts but I changed my mind and decided to do something a bit more complicated and settled on machining the steering arm castings. They've been lying around a while and are definitely aged enough.

This part is roughly equivalent to the upper triple clamp on a conventional motorcycle. Unlike an upper triple clamp this part is not subject to suspension loads, only steering forces. The dual drag link configuration is designed to transmit maximum feel from the front upright-wheel assembly to the rider's hands.

The raw castings are shown here with a fresh fixture sub-plate and the material stock for the mounting fixture:

I manually machined the 2 fixture blocks that would mount onto the fixture sub-plate and the part would be mounted on.

The completed fixture assembly is shown installed on the trunnion table.

It is a pretty simple fixture but does require locating pads and holes to be premachined on the castings. This is a simple enough operation that it can be done on the manual mill too:

Now the part bolts directly to the fixture and has one small preload bolt to eliminate chatter when machining the center bearing features.

In the 0 and 180 degree orientation we machine the center pivot bearing pockets, clip on mounts, rotary steering damper mount, brake reservoir mount, and logo. There's not much material removal so it only takes a few minutes.

I then index the fixture plate 90 degrees and machine the steering drag link bearing mount holes on each side of the part. This is another quick operation and proceeds with no problems:

That completes the part.

Now reload and rerun a few times and I have 4 machined castings ready to use:

That's all for now. I think the next part will be the front spider which will allow me to test assemble the upright assembly.

Helical Clutch Actuator

2011-10-18T20:06:00.000-04:00

This post will document the fabrication of the mechanism that converts the linear pull of the clutch cable to the motion required to release the clutch.

As this is one of the user interface elements of the bike some attention needs to be paid to the forces and leverages involved to be sure the clutch pull is not too stiff yet firm enough to allow the rider to modulate it a bit. This was pretty simple and I found a reduction ration of about 5:1, meaning that .5" of clutch cable pull should equate to .1" of movement of the clutch pressure plate.

Now that the desired leverage ratio was determined I needed to design a mechanism that fit the available physical space. As the clutch is protruding slightly past the frame on the right side of the bike I wanted to keep a low profile so that the actuator was not the first victim of a lowside crash. Several of the current Supersport bikes use a rack and pinion style actuator with the clutch cable tied to the pinion and the rack having a thrust bearing to mate with the pressure plate. This style is nice but is long. Being long does not matter for the I4 engine style as the outer cylinder is wider than the clutch/trans area but the extra length would not package well in my V4 configuration. I thought about using the self contained helical actuator from a SV650 as done with the custom slipper clutch for the Rotax single:

This design worked well but was a little long and visually messy as there were several external components that were not that pretty. It also was a bit difficult to properly seal and since oil on the rider's left boot is not a good thing I set this idea aside.

Knowing that I'd like to have about .15" of pressure plate travel (a bit extra is always nice to allow tuning of the slipper effect) I set about designing a thin actuator that provided the needed travels. I ended up with a very slim design that used roller bearings for all motions involved to minimize friction and maximize feel. One important design point was that I wanted to use a readily available clutch cable so spares were easily sourced and inexpensive. Since there are some Kawasaki OEM parts in the engine it ade sense to design around a Kawasaki ZX6R cable which is what I did.

The aluminum housing parts are already made so the helical actuator part is the only one left.

In this cross section through the clutch shaft you can see the details. the release balls are not visible but there are 3 of them in 3 matching helical grooves. As the clutch cable (shown in the first CAD rendering above) pulls on the grey part it pivots around the radial bearing while the release balls ride up in their grooves, thereby moving the grey helical actuator away from the engine. The gold connector rod then pulls the clutch pressure plate up with a thrust bearing sandwiched in between to allow rotation of the clutch.

You can see them and the helical grooves in both parts in the following image:

The design met its 2 primary goals well: a. slim design that needs less than .6"of thickness from the outside of the clutch pressure plate, and b. Smooth motion through the use of roller bearings on all motion axes. Now its time to machine.

So here we start with a couple of pieces of stock and a chunk of aluminum for the 2nd operation fixture:

Stock clamped for the first operation:

And the first operation complete:

The radial grooves were done using a 1/4" diameter end mill with a ball end and plunging in the Z direction while doing a G3 arc move. I used a .250" end mill but used 6mm (.236") balls to have a little clearance so that they no not bind due to the unavoidable manufacturing tolerances.

Now I made a fixture plate that this part could bolt to and ran the 2nd operation program:

I ran a 2nd part to have a spare. After welding the radial bearing boss on and a little manual machining for the cable end pocket and retaining pin and the part was finished.

You can see the rotary/linear action in this short video:

That's one more subsystem complete, next will be some internal shafting for the oil pump. these are simple parts so will be done manually on my Hardinge lathe and should be done in a day or 2.

Thanks for the contributions

2011-10-18T19:04:00.000-04:00

Just wanted to thanks those that were able to donate to the effort so far. It is greatly appreciated. I also wanted to say that there is no minimum donation, $50 is just the lower limit to get some swag. There are paypal fees deducted on my end so low single dollar amounts may only end up giving paypal some free revenue. YMMV.

Thanks,

Chris

Let's get things moving!

2011-10-03T18:49:00.022-04:00

Here's you chance to help us out! I've been moving along with the project as I can but progress can be much faster with your contribution. I want to try to get the engine running by the end of the January and we can get there but need your help. I've set up a PayPal address that will accept donations of any amount. You can click the button here or the donations button on the right side of the blog under the followers.

What I need is $25,000 to get the first 2 engines up and running. The money will be spent on the following items:

-3 of more sets of crankcase castings $3000

-finishing of 3 crankshafts: $4000

-primary drive gear grinding for 3 pieces: $1200

-Nikasil cylinder plating for 4 castings: $2200

-ECU/support electronics: $10,000

-dyno engine fixture: $2000

There's a little cushion in there for potential bumps in the road. These expenses are for outside vendor work and components. If I could I'd make this stuff in-house but in these specific areas it is best to go to the acknowledged experts in the field to get the work done right.

Donations of any amount are accepted. For a $50 donation you will receive a t-shirt and sticker. $250 gets your name on the fairing in 24 point type. Donations of $500 will earn an engraved name on the cases of the first and second running engine. Imagine how cool it will be to show up at a racetrack and be able to point out your name engraved on a racebike engine! I have not though about perks for gifts over $500 but feel free to test my imagination!

Regardless of how much comes in through these donations I am still moving forward as fast as possible with the project. I am currently throwing everything I have at it and will continue to do so.

Thanks for reading and following the project, your comments and readership help me to continue pushing for completion.

Another operation done....

2011-09-17T18:25:00.000-04:00

To keep the streak going I finished the clutch cap on the lathe today. The first milling operation went smoothly but this lathe operation had a slight bump or two in my way. I initially programmed the part using conventional tooling but the recessed pocket really needed some more specialized face turning cutting inserts. The problem was minor and did not cause any undue headaches but the program needed to be redone.

The first step was to cut some profiled soft jaws to hold the part:

The small burrs you see are away from the profile and will not cause any clamping problems.

Unfortunately I was on such a roll I machined all 3 parts without taking any pictures of the process! Here's the final 3 pieces looking really good:

The clutch side is nearly complete and looking great. I'll try to get to the oil fill and crank end plugs today then next week I have to do a bunch of contract machining so will likely be too busy to make bike parts. Damn. I will try to get to something done to keep the streak going.

Gettin on a roll

2011-09-16T17:51:00.000-04:00

Ahh, peace and quiet to make bike parts. As close to nirvana as I can get these days.

Today was a low hanging fruit, the clutch cable actuator cover. This is a cute little piece with the gear to wing logo and 2 versions of the name, "Cosomoto' and 'Cosentino'. I'm partial to Cosentino for obvious reasons but Cosomoto is just to close to Quasimodo. Either one, I'm covered!

Parts blanks and layout sheets:

Simple fixture plate:

Op 1 (top) and 2 (bottom):

2 pairs:

With the top surface finished out:

Next I'm going to finish up the clutch cap and machine the helical actuator and that will then let me assemble and test the clutch actuation mechanism.

It's great to see the visible progress. A running engine can't be far away.

Our 5 min of fame just went by.....

2011-09-15T20:55:00.000-04:00

As I mentioned in a previous post we had the guys from the Discovery Channel HD Theater over here shooting some footage for an upcoming episode. It turns out that upcoming episode just came up!

They are broadcasting it this week on the Discovery HD Theater channel. Its the show 'Cafe Racer'. Its Time Warner channel 767 in NYC. It's the episode with the description 'A junkyard chopper cradles a hidden gem; defense contractors tackle café racers; and a NY artist tries to exercise some two-stroke demons.' I'm not quite sure which one of those describes us but check it out, it should be on multiple times each day for a week or so.

They took a lot of footage for a couple of different episodes and since we have not seen it yet I'm not sure what part you'll see. I do hope it presents us in a somewhat decent light! Let me know what you think.

One more time

2011-09-15T20:18:00.000-04:00

Wow, nothing like a lack of paid work to allow me to get more done on the bike! Seeing that the clutch side is getting closer to completion I started on the clutch cap, the cover that also houses the helical clutch actuation mechanism. On race bikes it is crucial to be able to change the clutch plates easily so I did as many racebikes do and made the clutch cover 2 pieces: one main housing and one small cap that covers the friction plate area.

I had a rectangular block of aluminum that was plenty for 2 parts but just too small (I thought) to get 3 parts out of. After a bit of creative nesting I was able to make 3 blanks with parallel sides for easy clamping.

This part is different from nearly all the other machined parts on the bike in that it has a domed surface and curved stiffening ribs:

This makes machining more time consuming in that I have to sweep an end mill along the surface with a very small stepover. The end result is a light and strong part that also looks pretty cool because of the slightly visible tooling marks.

The process starts with a large stepover (producing pronounced scalloping due to the use of a ball nose end mill) and as the remaining material decreases the software reduces the stepoveruntil the remaining scalloping is at an acceptable level.

Large stepovers on roughing passes:

Gradually getting smaller:

Small stepovers on final finish passes:

The center area of the part is where the helical clutch actuator will be. The 3 small arc shaped cuts are helical paths that will have a stainless steel ball installed in. A pivoting plate with mirror image grooves will mate with it and when the plate is pivoted by the clutch cable the balls will ride up in the grooves and pull the outer clutch pressure plate away from the friction discs, thereby releasing the clutch. It's not exactly easy to explain but does work.

I was able to get 3 useable parts from the single block of aluminum, one with a weird surface finish due to improper software settings in the finish machine operation. It does not affect the part's function and can easily be remachined once the back surface with location features is done.

This part is also unusual in that it will require one mill and one lathe operation instead of 2 mill operations. The outside of the part is suitable for milling but the inside of the part is a simple revolved surface, making the lathe the appropriate machine to use. I have a bunch of lathe work to do next week but can hopefully sneak this part in over the weekend.

See you soon.

Finishing the clutch cover

2011-09-12T18:33:00.000-04:00

What a productive week for the bike! I was able to get some more time in on the mill and complete the machining of the clutch cover. The last operation on the part was machining the interior pockets, profile, and starter gear mounting features.

The next step is to make a fixture plate that can locate from these previously machined features then bolt the part to it and finish the outer surfaces.

First, I machined a plate with some dowel pins to accurately locate in the machine table t-slots:

Then I ran a second program that drilled a hole pattern to match the mounting and alignment holes of the part:

I then bolted the part to the top of the fixture plate using the expendable bolt holes made in the first operation:

Holding it like this will allow me to run the first half of the program, pause it, reclamp the part using the perimeter mounting holes and remove the large fixture bolts, then resume the program and complete the part:

Notice how the large circular part left in the previous operation has now dropped out off the final part.

Repeat those steps and I ended up with 2 good parts:

I bead blasted one to see how it would look and while the part looks better once you assemble it next to the crankcase cast surfaces the billet one seems more appropriate.

The blasted one is too close to the cast surface finish without being the same. Cool, but I like the billet. Maybe I'll have the blasted one color anodized once we get a better idea of the overall color scheme of the first bike.

Next part is the clutch cap that bolts to the outer large circular boss and contains the helical clutch release mechanism. Hopefully this week will have some time for me to get to it.

After bolting this part on I'm realizing that we're not too far from a complete engine! Wow. Time to knuckle down and make it happen ASAP.

Clutch cover machining

2011-09-08T23:09:00.000-04:00

Now that I'm done with the pockets on the primary drive gear there is some empty space on the mill bed so I'll get in come clutch cover machining in while the setup is available.

After machining the 4340 steel going back to aluminum is a pleasure. The 4340 steel is a high strength steel that requires a rigid setup with speeds (how fast the spindle/cutting tool spins around) and feeds (how fast the cutting tool is advanced through the material) about 1/3 that of aluminum. If cutting aluminum can be compared to a hot knife going through butter you can describe cutting high strength steel as a butter knife going through steak. A tough stringy steak, not a nice tender filet mignon. One that quickly dulls even the hardest coated carbide cutting tools.

Back to the topic at hand, cutting aluminum. As usual we start with a large flat plate clamped to the table and gradually whittle away all the unnecessary material.

Careful clamping and slightly thicker stock will allow me to leave a thin bridge of material around the perimeter making it easy to clamp and machine without clever fixtures.

All the programming was correct and this operation went off without a problem.

The large circular island in the middle of the part is where the clutch will go. This island was left to allow me to use the hole as an initial clamping point for the second mill operation. When the last facing operation is done the round dropout will become scrap.

I ran two parts and checked fit of the starter shafts and gears that this cover houses and everything fit properly.

I now have to program and run the fixture plate for the second mill operation then program and run the front side of both parts. That will finish the part and allow me to start mocking up the starter gears and right hand side engine components. Hopefully I can get to that in the coming week and put up another post.

Finishing the primary drive gear

2011-09-07T22:42:00.000-04:00

After the two lathe operations to create the primary drive gear blank I need to do one mill operation to create the clutch basket mounting holes and various weight reduction features.

Switching from machining aluminum to machining steel is like getting a 2 flat tires. With aluminum you can spin the spindle as fast as it can go and then just push the end mill though the material with little regard for cutting forces or temperature. Chips fly and progress is made, quickly. With steel, especially this high strength 4340 material, the spindle needs to slow down a lot and the feed rates seem to be just above a crawl. End mills wear quickly and if you're not careful with the cutting parameters you will be treated to the sight of a glowing end mill spitting out glowing chips. Pretty, but not good for material integrity.

To hold the part I machined soft jaws (similar in concept to the lathe ones) in the Kurt vice, clamped the part, and indicated it for concentricity just to be sure.

After setting up a set of the same tooling used to machine the crankshaft journals we're ready to run the program. It is not too complex a program, just some holes and pockets. The finished part looks like this:

and after repeating a few times we have a nice group of parts:

The parts are now ready to be sent out to the gear house who will cut the gear teeth on the outer diameter of the part. It will then go for plasma nitriding to surface harden it and after that the part is ready for use.

Tomorrow I'm going to switch back to aluminum and start machining the clutch side cover.

Making parts again....

2011-09-06T22:58:00.000-04:00

After a couple of weeks of turning these

into a bunch of these

and a lot of this

the lathe is open and I am more than ready to make some bike parts!

Today we're making the blank for the input shaft primary drive gear.

This is the large spur gear that the clutch basket bolts to. It meshes with the crank drive gear which is machined directly onto one of the circular crank counterweights. This is a highly loaded part and therefore made from the same 4340 material that the crankshaft is made from. The plasma nitriding hardening used to harden/strengthen the tooth surface is the same process used for hardening the crankshaft plain bearing journals. Due to the higher surface stresses encountered by the gear tooth the part will be left in the plasma nitriding chamber for a longer time which creates a deeper layer of hard material.

The process will start with round blanks sliced from a 7 1/2" diameter bar. The material was sourced from Grammer Dempsey & Hudson, a ferrous metal (steel) supplier located close by in Newark, NJ. They are old school to the point that they don't have a website!

Here's a few blanks of material are ready for the first and second lathe operations:

After machining soft jaws to the appropriate diameter the stock can be held in the 3 jaw hydraulic chuck. Soft jaws are replaceable clamping jaws that can be easily machined to hold a specific part diameter or profile.

I then ran the first lathe program which cut the clutch basket mounting face and pilot, the needle bearing bore, and the outer diameter that the gear teeth will be formed from. Machining all the crucial features in one setup ensures a high degree of accuracy. Since this part is responsible for the transfer of all the engine power from the crank to the transmission accuracy is essential to minimize frictional power loss.

After machining several parts I then recut the soft jaws (they are replaceable once cut down as far as the mounting bolts) to hold the part by the newly machined outer diameter in order to clean up the back face of the part.

The back face machining is for weight reduction only so accuracy requirements are much lower than for the front functional surfaces but I still take care to minimize reclamping errors..

Repeat a few times and we have enough for a first run of engines:

The part now needs one mill operation to create weight reduction pockets and the clutch basket mounting holes. I should have some time this week to do that.

Cross Pollination

2011-09-05T15:08:00.002-04:00

Just letting the blog viewers know that there is a new thread on the project over on the ADV Rider Forum. The forum is mainly focused on Adventure riding. They describe their mission as 'created to support the horizon-chasing adventure motorcycling community.' It's a far cry from roadracing but it uses motorcycles and it's practitioners are more likely to take a hacksaw and wrench in hand to improve functionality than most riders are. Also, adventure riding is fun as hell and a lot more accessable and cheaper than roadracing. Pick a dirt road and go.

The site's new 'Some Assembly Required' forum is a perfect place for the project and so far it has gotten a warm welcome. Take a few minutes to browse and you'll see an interesting collection of projects and maybe get the bug to find the horizon.

I have a bunch of pics to put into a couple of posts but my camera is still making its way back to me after our Indy trip, which was a ton of hard work with barely a second to relax.

Check back in a day or so for more.

Nice Surprise for the Weekend

2011-08-25T23:58:00.000-04:00

And I don't mean Hurricane Irene! On short notice I was offered a ride to the Indy GP and a free paddock pass! Imagine how long it took to reply 'hell yes!' So instead of hell and high water keeping me away from an event, the hurricane will hit NYC long after we're gone. I'm going with a group involved in a still not yet finalized Gary Nixon tribute. We'll be in the garage area behind Gasoline Alley (I like the sound of that) all weekend, likely the only ones with a blue ex-Nixon triumph. I'll be the guy trying to sneak into each MotoGP garage and get close up shots of the bikes!

If anyone within range of this post will be there drop by and say hi.

Here's to a great weekend of racing at the Brickyard.

Oh, next week I'll be doing a bunch of bike work so more posts are in the pipeline.

Chris

Article in Roadracing World

2011-08-19T21:56:00.000-04:00

There is a 3 page article in this month's edition of Roadracing World Magazine, the best US print magazine covering everything from club racing to WSB and MotoGP action. The full name of the magazine is 'Roadracing World and Motorcycle Technology', making their coverage of my project even more appropriate.

I spent some time on the phone with writer Michael Gougis and then send him a load of images and web references. Out of that jumbled download he was able to craft a great summary of the project starting from my introduction to roadracing on a vintage RD350 air cooled 2 stroke through to blogging on the V4.

If you don't have a subscription you can check the magazine out at most motorcycle parts and accessory stores or you can go online and view this month's issue electronically on their website.

This week I will get some time and be able to machine the clutch cover and maybe a few other small parts so keep an eye out for an update.

Chris

Some manual work for a change

2011-07-21T17:18:00.004-04:00

What to do when it's baking out? I know, weld some parts! One of the myriad custom small parts for the bottom end of the engine is a double gear for the electric start system. Yup, when my rider has rare occurrence of hitting the pavement (of course due to some other rider's error) they'll be no yelling at recalcitrant marshals for assistance here. A press of the magic button and the bike will start right up and be back in the action.

Several of the electric starter components are sourced from various OEMs and this double gear is one of them. It needs to have an increased separation between the gear faces than the original part. To accomplish this I'll start with 2 complete gears, machine one face off of each, then weld a spacer in between with the appropriate jigging to keep both gears and bores properly aligned.

Original gear:

Machining large ring from one part:

Gears machined apart and spacer ring prior to welding:

Assembly pressed together:

and welded:

I used a Miller Syncrowave 250 TIG welder using stainless rod to join the gear pieces with a piece of 1018 steel. This should provide a weld that is not too hard and does not have too much alloying element diffusion. I took care to keep heat input to a minimum to avoid losing the hardness of the teeth and let the part cool very slowly to prevent cracking. The part looks good and both gear faces run true so I can take one more part off the to-do list.

I am waiting for some metric 5C collets to arrive then will finish the oil pump shafting and some other various simple round parts like front suspension arm inner races and rear swingarm link and pivot races.

Chris

Back to our scheduled programming

2011-07-16T19:46:00.002-04:00

After the hustle of the past few days it was nice to get a quiet day at the shop. I was able to successfully assemble and test the complete transmission and shifter assembly. After doing a couple of simple manual 2nd operations on the part (deburring, threaded cross oil hole passage) I pressed the bearings in and assembled and carefully checked the drum and shifter fork alignments to assure smooth shifting performance.

Pressing the bearings in with a medium sized C-frame press.

Bearings in and parts ready to go.

Shift drum detent spring and stop in place.

Shift drum bolted in.

Shift forks and rods.

Primary and output shafts, assembly is now complete.

Another view.

Transmission, meet girdle. Girdle, say hello to transmission.

Very nice. Fit was perfect and this is one more assembly towards a running engine. It felt good to make some progress in the past weeks and I hope to continue the run of productivity!

Next update will document the machining, testing, and assembly of the various shafts, gears, and gerotor for the oil pump system. Once this is done I can test the setup and verify that the pressure and volume delivery characteristics of the pump meet my design specifications.

Keep an eye out for another update soon.

Chris

5 min of fame

2011-07-16T18:55:00.002-04:00

The post couple of days here at the shop have been a bit different. Through AHRMA racer Kenny Cumming's contacts we've had the film crew from Velocity (formerly Discovery HD Theater) filming footage for a couple of episodes. Kenny was behind the development of my vintage fork upgrade kit and is a consistent winner with multiple AHRMA championships on his trick Seeley Norton.

One episode will be based on trying to do the ton on a new Royal Enfield at Beaver Run racetrack near Pittsburgh, PA. We helped out sort the suspension a bit for high speed operation and tried to remove all the excess equipment on the bike. I would have preferred to do a more comprehensive performance build but time limitations and available parts were extremely limited. I think at least now it won't throw the rider off!

The second episode focuses on the bike space a few friends and I share and will have break outs with each of us individually and I get to talk about my project more directly. It was fun and although there were no shouting matches or fistfights it should be worth watching. I'll make a new post when they finalize a broadcast date.

Chris

And Back to the Mill

2011-07-15T23:53:00.001-04:00

Just got some more time on the mill to finish out the cassette transmission plates. The last post on these ended with the first operation complete. The next steps are to machine a fixture plate and then run the 2nd operation which includes boring the bearing seats to final size with a +.0002/-0 tolerance. That's pretty tight, about 10% of the thickness of a human hair.

Here's the fixture plate, a piece of MIC-6 cast aluminum ground tooling plate with dowel and mounting holes:

Here's the part after finishing the profiles and roughing the bearing bores:

Now I'm finish machining the bearing bores with the custom boring bars ordered from Microbore:

The reason I am using such a long tool for this operation is that the same bore sizes need to be machined deep inside the lower crankcase girdle casting. By dialing in the size with these shallow parts I can use the same tool later on when line boring the block and be sure the bearings have a consistent fit. The primary and output shaft and shift drum bearings were all single point bored to size with these long tools.

Tomorrow I'll do a test fitting of the gears, shift drum and forks, the shifter pawl assembly and try to stuff it all into the crankcase girdle casting. Look for another post soon as the bottom end starts to take shape.

Chris

When the mill is busy....

2011-06-17T22:56:00.002-04:00

Switch to the lathe. Got a bit of time in to make some parts for the front end, specifically the steering stem. Although my bike does not have forks, it does have a steering stem, one that moves with suspension travel but does not pivot with steering. The design is a throwback to my original Mk1 chassis that used a combination of tapered roller and deep groove ball bearings instead of spherical rod ends at the upright pivot. Sorry for the vintage shot but those were the early days of digital.....

Those were the early days (2001) of nearly zero rake and an air cooled Rotax single. In case anyone was wondering, do not use Daytona as a maiden voyage for a race bike, frame still warm from welding. We both survived but it was a lesson learned!

I've almost come full circle, having experimented with various bearing configurations in the quest to maximize feel and minimize friction and hysteresis in a compact package. This is an area in front end design where just equaling the feel and feedback quality of telescopic forks will be a very good result. With a linkage and multiple pivots there are many more areas where the vibrational energy that is feedback can be lost. Careful detail design can minimize this loss and is a necessity for high performance race applications but the solutions are not always obvious. For a while I was using high quality Aurora spherical rod ends that gave me easy adjustability but lacked in extended lifespan and were relatively expensive. The bearings in the current version are different styles from what was originally used and should be an improvement in feel and packaging.

Back to today's part, the steering stem. It serves to connect both suspension a-arms and provides a pivot axis for the wheel/legs/upright assembly. It has 2 bearing journals that define the steering axis, a jam nut thread, and 2 cross holes once for each a-arm.

Herre's the bare part:

The first step is to turn the main part geometry from bar stock on the CNC lathe.

Close the door, press the button and...

Open the door and presto, a part:

To assist in getting the bike dialed in I had to make several different versions of the stem. Think of them as different triple clamps and you won't be far off. In combination with other interchangeable parts they allow near independent adjustment of several important chassis parameters.

Here's the 3 different part geometries with the steering bearings that will be used.

These parts will now need to go into a 4th axis mill setup where I will add the flats and cross holes, finishing them.

That's all for now.

Finally another update

2011-05-21T23:14:00.001-04:00

Sorry for the extended interval since the last update. I've been trying to get as much paid work as possible while it is available, the life of an independent is feast or famine, and there hasn't been much feasting lately!

Anyway I was able to get some extra time and sanity and made some progress on the transmission cassette cover. These parts are made from a billet of 7075-T651 aluminum. They hold the two transmission shafts, the shifter drum, 2 shift forks and shafts, and the selector mechanism. The transmission design allows the entire assembly to be pulled from the clutch side of the engine without having to do any other engine disassembly, making for easy ratio changes. As we are using Kawasaki transmission parts there are several available ratios from the race kit.

Here's the 2 blocks of 7075 waiting for machining:

No fixture needed for this first operation, just a wide open vice:

This side of the part was pretty straightforward, no special machining operations needed. The next side will bore the bearing pockets using some of the custom boring heads I had made. After about 15min of machining you end up with 1/2 a part and a lot of chips:

Now insert the 2nd billet and repeat:

I'll be machining the other side sometime in the next few days so an update should not be an extended wait. I hope to be able to put a big push in the coming month and get this baby running ASAP.

That's all for now.

Chris

Back from Daytona

2011-03-14T21:49:00.002-04:00

Just got back from Daytona and had a great time enjoying some nice weather and motorcycle racing. What more can one ask for? Well, we can ask for the AMA to properly run an uninterrupted 200 mile race like they used to be able to do. This makes it 3 years in a row with screw-ups. Mandatory front tire change? That's a big ball to be dropped by Dunlop. When a company signs up to provide equipment for a spec series that equipment should not fail, potentially putting riders at risk of injury. I saw PJ Jacobson's tire after his crash and wondered how squirrely the bike must have felt on the banking with missing chunks of rubber. Not confidence inspiring to say the least.

Back to fun topics. While we were there I toted the engine around the paddock and showed it to several people and got some interesting feedback. The sweet engine stand was whipped up by Scott Kolb, as usual filling in the aesthetic gaps I leave.

We met with Barry Gilsenan and Eraldo Ferracci, both of who were impressed with the progress so far and excited to get to a stage where they can actively help the project move forward.

We also met with Skip Dowling, president of Orient Express, to thank him for the sponsorship on engine parts, both OEM Kawasaki and aftermarket, that he is providing. All in all it was a productive trip and now I'm inspired to get this motor running ASAP.

That's all for now.

Trip to Daytona

2011-03-04T22:52:00.001-05:00

As with hibernating bears, hibernating motorcyclists eagerly await the first glimmers of spring to start the trek to Daytona, the first major race event of the year. This year I am lucky enough to get some free time and head down there with Scott Kolb and his Bonneville LSR team. In addition to spending some time relaxing in warm weather we will be hanging around the Celtic Race Team's garage to lend a hand if needed. Barry scored a big win this year in partnering with Fast by Ferracci to run Ducati's 848EVO in the Daytona Sportbike series. This bike is a sweet track tool and Barry's rider, PJ Jacobsen, showed just how much the competition should be worrying by topping the timesheets at the Daytona tire test.

In the interest of making this a more interesting trip I spent some time getting the engine assembled into a convincing looking long block while Scott whipped up a sweet wheeled engine stand. We'll be hanging out in the paddock with the engine trying to get some exposure in the AMA scene. If we're lucky we'll get some time in the Celtic pits with Eraldo Ferracci and see if he has any words of wisdom on our project. If you see a coupe of guys wheeling around an engine with no bike attached, stop by and say hello.

Sorry about the crappy cell phone picture but I was rushing to get the engine assembled in time to put it into Scotts' trailer for the trip down to Florida. I don't think we would be able to bring it on the place as carry-on luggage!

Machining the Oil Pump Cover

2011-03-04T22:28:00.002-05:00

This installment covers the machining of the oil pump drive housing but first a little background on the oil pump/system design.

There are three main types of oil pumps to choose from: plunger style, spur gear style, and gerotor style. Plunger style pumps have been made obsolete by the improved gear and gerotor style pumps so will immediately be discarded. A couple of images showing the gear and gerotor style pumps can be found at this link. Since I've never designed an engine oiling system before I tried to find an expert to assist me. A few phone calls to some noted engine tuners all pointed to the same source: Marc Goulet. Marc, formerly of Nichols Portland and now at Melling Engine Parts, Inc., has extensive experience in designing performance engine oiling systems. He has done systems for various F1 cars and several MotoGP bikes, including the Ducati Desmosedici. Needless to say, this is the person I was looking for. Marc was extremely helpful, first educating me on some of the details of oiling system design, then critiquing my designs until we came up with a system he was happy with. His first recommendation was to go with the gerotor pump style. Less oil abuse and higher efficiency were all it took to convince me. There are a lot of details to be considered, some of which cannot be ignored under pain of complete oiling system failure, some of which when ignored result only in a slightly less efficient system. I wanted to cover all the bases: have a reliable and efficient oiling system that provides just enough cool, clean oil to all of the appropriate components while using a minimum of power. A design guide from Nichols Portland was a big help in getting the design in the ballpark. The guide is available online here if you fill out your personal information.

The first step was choosing an appropriately sized gerotor pair that had existing tooling. We were able to use one of Melling's stock products as shown in the following photo:

After several revisions we had a system Marc was happy with: generously sized inlet porting to minimize filling resistance on the inlet side of the pump, appropriate porting and venting to prevent unbalanced operation, and a large and strategically located bypass valve to reduce unnecessary pumping losses. Now that I had a good design, it needed to be fabricated.

Half of the pump housing and port geometry was located in the girdle casting as shown in the following picture:

The gerotor outer rotor sits in the main pocket and the inner rotor is eccentrically mounted and driven by a gear reduced shaft from the primary drive gear. The machining of this has already been reviewed so we will move on to the cover plate machining. The cover plate serves several functions: it has half of the inlet porting, outlet shadow porting, outboard drive shaft bearing support, and appropriate venting to prevent undesirable pumping losses. It also seals the jackshaft bearing and gerotor pocket from leaks.

The machining process is a repeat of the technique used so far: machine the functional side of the part from an appropriately sized billet, trim the excess off with the bandsaw, then machine soft jaws, flip the part and machine the external surfaces.

Here's the billet being held in the vice prior to machining:

Here's the part after the first machining operation:

The large boss/pocket on the left side of the part matches up with the porting in the girdle casting to provide a leak-proof path through the gerotor.

From here I machined soft vice jaws to hold the part from the 2 circular bosses then faced and pocketed the external surfaces as needed.

Repeat as needed and I ended up with 3 finished parts that look great and are all well within tolerance:

That's all for now. The next installments will be on machining the crankshaft cam drive sprocket teeth and some more of the engine side covers.

Until next time......

Finishing the Generator Cover

2011-02-18T15:00:00.002-05:00

I managed to stay late and squeeze in some more machining to finish up the generator cover. After ending the last post with the first setup finished I then machined a simple fixture plate to locate on the interior features of the part. it used the stator mounting bolts and a couple of mounting holes with dowel pins to keep the part accurately aligned with the previous operation.

Second operation fixture plate:

Loaded in the mill with a part installed:

After rough machining:

With it's brothers:

I gave one a light glass bead blasting to reduce the reflectivity of all the shiny machined surfaces. The result looked great:

The round cap part has M50x1.25 metric threads that were made on a lathe with a normal threading cycle, like most externally threaded parts. The cover part then needed an internal M50x1.25 thread which would need a special M50x1.25 tap, which would be very expensive, or I could make the thread using a thread mill, which is the option we used. Thread milling uses a 60 degree V-shaped cutter that is moved in a helical path that corresponds to the thread profile. If everything is done properly you end up with a very clean and accurate thread without the need for a tap.

Here's a video of the thread milling operation. It is done 3-4 times with an incrementing depth of cut and a small finish path.

These parts are now finished and the next step is to make the gerotor pump and bearing shaft cover. Look for a post sometime next week for more.

Until next time.

Starting on the Generator Cover

2011-02-17T16:02:00.001-05:00

Back to making chips! This post is the first part of fabricating the generator side engine cover. this is a 2 piece cover with a threaded inspection port to give access to the end of the crankshaft.

I'm doing the same process as used with many other parts: first machine the inside surfaces from a billet of aluminum, then in a following post I'll machine a fixture plate that locates to these features and then machine the external surfaces of the part.

The internal features and mounting holes are critical to the correct placement of the stationary stator with respect to the crankshaft mounted rotor. By machining these in one setup I am assuring high accuracy between these features.

Skipping directly to the chase (I forgot to photo intermediate machining steps!) Here's 3 sets of parts: 3 completed access ports and 3 1/2 machined side covers.

Threaded inspection port:

This was a 3 operation part: first turn the thread, counterbore and o-ring sealing groove, then turn around and turn the outer profile, then switch to the mill to make the 17mm hex for wrenching.

Generator side cover at the halfway mark:

This operation created the outer profile, mounting and locating holes, and mounting holes for the Electrx race stator. This product from Electrex is a low profile race generator kit meant to replace the larger systems found on production Japanese motorcycles at about 1/5 the cost of a similar race kit item from any of the manufacturers. Build quality was excellent and they are great source for low volume OEM sourcing of generator components.

Here's the stator bolted in place with the 3 phase wiring exiting though a slot in the gasket surface:

Next up is capping the ends of the valve covers and then final machining of the welded cylinder heads and valve covers.

Until next time.

Kolb Comes Through

2011-02-12T13:29:00.002-05:00

Many thanks to Scott Kolb of Kolb Machine for delivering 2 perfectly capped and smoothed cylinder heads. Scott is a fabrication ace and it is him who I turn to when my ham-fisted hand work simply will not be up to snuff. He is also an accomplished builder in his own right, having several land speed records under his belt and several more in his sights. His blog site shows a lot of cool stuff on his LSR project. There is also some great footage from his visit to the A2 wind tunnel in North Carolina, the heart of NASCAR territory. The visit was very productive and informative for both learning about his existing partial streamliner and doing tests on shapes for his future 200+mph 125cc full streamliner. It was my first wind tunnel test and hopefully not my last.

I had 2 sets of ported heads and kit cams purchased from Attack Kawasaki from one of their last Formula Xtreme bikes when that series still allowed significant engine modifications. These heads were sectioned on a bandsaw and cleaned up on the mill to leave the camchain tunnel and adjacent 2 cylinders.

Bandsaw cutting:

Cleaning up surface on mill with face mill:

I then stripped the paint off the parts and shipped them up to Scott. He proceeded on the 2 step process first documented in an earlier post, Head Weld Test. The 2 piece cap is to insure the internal separation from the oil and cooling passages remains separated.

Cutting out the cap plates:

Top cap plate unwelded/welded:

We installed extra valves and springs during the process to ensure the valve seats did not slide out of position due to the high heat input during TIG welding.

Fully welded part:

We decided to also fill in the cam bore 1/2 circular cutouts to make the gasket surface a single plane to allow using a waterjet cut Cometic gasket

Filling in cam journal external bosses:

Fully welded:

Trimmed:

Scott then ground out all the welds giving the part a very clean and manufactured look.

From here I will remove the valves/springs and mount the head on our trunnion fixture to clean up the gasket mounting surface. Some custom gaskets are on the way from Cometic to keep all the oil inside and we're a few steps closer to having a complete engine.

Until next time...

Machining the Crankshaft Connecting Rod Journals

2011-02-10T20:53:00.000-05:00

I was able to get some more time in on Peter's mill and got the journal machining done on all 3 crankshafts. After the last step the cranks were turned but did not have the offset journals machined, as shown in the following picture:

This step moved the parts from the lathe to the mill. I hold the right side of the crank in a 3J collet and supported the outboard side with a tailstock with a dead center. The setup is shown in the following picture:

The process is the same as the aluminum test part, except the spindle speed and feeds were much slower, the depth of cut was less, and I used a roughing and finishing end mill. The finishing end mill was custom ground to have a flat end which minimized the uneven surface that the test part ended up with.

The roughing end mill has a serrated cutting surface and provides an aggressive edge to remove large amounts of material, allowing the finish end mill to only remove the last .02", last longer, and hold tighter tolerances. The end mills were purchased from Mari Tool and held in a 3/4 milling chuck for maximum rigidity.

Now on to some cutting shots. First roughing in a step pattern produces a square journal:

Once both journals are roughed out leaving a square the next operation employs a 4th axis move to create the rounded thrust and journal surfaces:

Here's a couple of videos showing the finishing passes for both the thrust and journal surfaces:

and

The resulting surface finish and accuracy were excellent. Here's a quick spin of the final part.

The great part about CNC is now I ran the same program 2 more times and ended up with 3 great parts.

Next steps for the crankshaft are to machine the camchain sprocket teeth and drill the oil holes. Hopefully i'l get to those operations next week and be ready to ship them out for gear hobbing and plasma nitriding shortly after.

That's all for now.

And now for something completely different

2011-02-07T20:52:00.001-05:00

After working on all these engine parts I got a bug to shift focus and to make some inroads on the pile of chassis parts that need to be made. My first choice was to make the upright legs for the front suspension. These legs are central to the variable flex idea that is incorporated in the front suspension. Instead of following the current ideas on overall bike flexibility which uses stiff telescopic forks and a slightly flexible chassis, I prefer to have the flex where it is needed-at the wheel. Telescopic fork equipped bikes don't have much of an option here- the forks needs to be relatively rigid, otherwise they would bind up when flexing under braking load, preventing smooth suspension movement. With the linkage suspension I am using it is possible to have a very stiff chassis and a-arm structure to allow smooth suspension action and accurate wheel location yet have flex built into the upright legs to accommodate small bumps and irregularities in the surface when leaned far over.

From the years spent campaigning my single cylinder racer I have a good idea of the directional stiffness that will produce good results. No, I won't go into specifics here on what the stiffness ratios are. As expected, maximum stiffness is needed in the braking direction and much less needed in the transverse direction. The initial uprights I designed worked well, but was a bit complex to make quick copies of. I then moved on to a much simpler design using rectangular steel, some with welded on stiffening plates to tweak the stiffness as testing dictated. The latest version of the front suspension uses some old and some new to result in a low friction assembly with easily characterized controlled flex characteristics.

First upright design using suspended headstock design:

This design worked very nicely but was a bit complex to make variations on. The suspended headstock and all ball bearing upright mounts provided smooth action and good feel but at a weight penalty to later, simpler designs.

Second design style using spherical bearings (bearings not shown):

This design had the benefit of being easy to replicate with subtle stiffness variations but I found the spherical rod end bearings reduced feel and required frequent replacement in order to maintain optimum performance.

Final version for the V4 project bike:

This version separates the parts into a bearing carrier and legs that bolt on. It enables easy modifications to the stiffness by making new leg parts with varying dimensions yet keeps the bearing mount arrangement stiff. The weight is in between the first two designs, a good overall compromise in my opinion. The upright legs will be machined today.

As with most billet parts I started with a large plate that both parts could fit in. I bolted this directly to the CNC table and machined the mounting pads and axle holes as shown in the following image:

I then machined a fixture baseplate that would locate on these premachined features and allow me to complete the part:

The fixture locates on the machine table with dowel pins allowing easy and accurate setup for making more parts.

I then cut out the individual parts leaving extra stock around the perimeter and bolted them to the fixture plate as shown:

Next came the pocketing and chamfer operations:

Resulting in a sweet looking part:

Mirroring the toolpaths allowed me to create the 2nd part with a minimum of hassle resulting in a very stiff looking assembly: This design also makes use of the latest radial mount Brembo billet calipers for the ultimate in progressive braking feel.

I don't mention it often enough so a big thank you goes out my shopmate to Peter H. for allowing me essentially unlimited use of his 4 axis CNC mill. Without access to his machine I'd be making much lower quality parts on my old BP 3 axis relic. And I'd still be figuring out how to fit the engine castings on it!

In the next few days I hope to move on to the upright bearing housing and handlebar mount, both of which need the 4th axis and trunnion table.

Until then.....

Initial Assembly testing

2011-02-02T21:31:00.002-05:00

After the rush of the holidays and new year I was able to get more time in on the engine. I did some long block assembly tests to check fit of all the reciprocating parts. All the parts fit properly and go up and down as the crank goes round and round.

Main bearing/conrod journal assembly

The 180 degree crankshaft was chosen to minimize the fluctuations in reflected crankshaft inertia torque. This is similar to the idea used in Yamaha's M1 GP bike and R1 street bike. Normal I4s have a flat crank which means that when the outer 2 pistons are at TDC the inner 2 pistons are at BDC. This results in the reflected torque of the entire piston/conrod assembly varying greatly. At high engine speeds variation can be up to 20 times the combustion torque. Because this variation is both positive and negative this variation of course does not add to the engine's output torque. What is does do is overlay a large amplitude noise signal over the small amplitude torque signal, muddying the rider's connection between the throttle and rear tire. This Youtube video from Yamaha does a good job explaining the difference in the 2 configurations. At around 2:30 the details of the inertia torque variations are explained. Yamaha's Furusawa wrote a technical paper analyzing the signal to noise ration of various crank configurations which backs this up.

Where I am departing from the status quo is my choice for a screamer firing order. I am proposing that the minimized crankshaft inertia torque variations is the real reason that Ducati twins seem so much more driveable than the other I4s in WSB. Single crankpin vee twins by default have a much better crank inertia situation than the normal I4 because of the piston/cylinder bank angle relationship. I think the whole 'big bang' theory is rubbish and therefore am trying to get the best of both worlds- low crank torque inertia variation for improved driveability but a screamer firing order for maximum power potential. There is a small penalty of having to add counterweights to the crank to reduce the rocking moment produced by the 180 degree crank arrangement but I think the benefits will far outweigh the costs.

You can see the details of this in the following 2 pictures:

The front bank cylinders are at TDC and BDC while................

The rear bank cylinders are both at midstroke. This configuration results in a minimal variation in crank inertial torque and I hope a clean signal from the rider's wrist to the crank.

You can see the interplay of the pistons in this short video:

Next up is checking out the camchain runs and doing a longblock assembly test with the cylinder heads and cams. Once this is done I can send both crankcase top parts to Millennium Technologies for nikasil plating and final honing. While the parts are being plated and honed I have plenty of smaller parts to make, various shafts and both engine side covers.

That's all for now.

Crankshaft Offset Journal Test Part Machining

2010-12-08T17:25:00.001-05:00

We left off on the crankshafts with all the lathe operations being complete and all 4 parts being ready for the 4 axis mill work.

The next operation is to do the offset machining needed for the connecting rod journals. There are two techniques available: eccentrically mount the crankshaft in a special chuck on the connecting rod axis and turn the journal or mount the crankshaft on the main journals and eccentrically turn the conrod journal. The first option is easier to program but more difficult to fixture, is very unbalanced during machining, and requires part repositioning for each conrod throw. The 2nd option is more complicated from a programming perspective but is easier to fixture, is balanced, and needs no part repositioning. I chose the 2nd option as once the upfront programming work is done making multiples is easy and repeatable.

Due to the low cutting forces due to the aluminum test part material and a desire to get a sample part machined I opted to leave the outboard 4th axis support off. Machine time these days is limited and getting a sample part quickly was of prime importance.

The mill setup is as shown:

The first operations are simple pocketing to remove the majority of the material in the most efficient machining technique. Pocketing was done at increments of 90 degrees and ended up with squarish journals.

Here's a short movie of the squared off journals:

Once this stage was complete I moved on to the 2nd program which created the fully round journals. The video of this move is subtle but cool. The machine is performing a G3 arc in the YZ plane (G19) while the 4th axis is doing a rotary move from 0 to 360 degrees. The result is an eccentric true cylindrical surface with none of the approximation concerns usually associated with surface machining type toolpaths.

This is the first journal after its finishing pass.

And this is a short movie of both journals.

The 3 slight ridges on each journal are an artifact of the dished end of the end mill used for the test cut. For the final steel parts I had a 4 flute finishing end mill specially modified to flatten the end face and keep it center cutting. It is not suitable for machining aluminum so in the interest of quickly getting a verified program I used a mill with standard aluminum cutting end geometry.

This part is being sent to a grinding house for finishing of the journals so the absolute tolerance and surface finish are not as crucial as long as there is enough stock left to clean up during grinding. After consulting with the grinder I am leaving .010" of stock on the main journals and .020" on the connecting rod journals as grinding allowance.

Now that I have a sample crankshaft we can test assemble a short block with the major rotating components: crank, conrods, pistons, and also trans and oil pump/drive components. Once we reach that stage there will be lots of pictures!

That's all for now.

Chris

Machining the Torque Plate

2010-12-07T16:17:00.000-05:00

I was able to get at Peter's mill for a bit last night and did the machining on the torque plate. This part is used during the final cylinder honing process to simulate the distortion of the bore caused by the cylinder head bolt forces. It is useless to create a perfectly circular bore if you are then going to distort it with clamping forces. This procedure creates a more accurate simulation of real world use during the bore process that results in an out of round cylinder when unclamped that shifts to round as it is clamped. I've heard that extreme tech engines like F1 do the honing process with a torque plate while the block is heated with hot water to even more closely replicate actual operating conditions. I'll have to see what MT thinks about this one!

The part started with a piece of 1" thick 304 stainless steel plate that was waterjet to a rough profile by North Eastern Water Jet. Andre of NEWJ is always very helpful in suggesting material they already have in stock to shorten lead time and reduce cost. The cost of the waterjet cut blank from NEWJ was less than a comparable piece of stock from the local supply house and saved me from having to hog out the majority of the cylinder bore.

The machining of the bores and screw/dowel holes was uneventful. The part is now nearly finished. The last issue is that the mill finish on the top of the material is not fine enough to clamp on the head surface without marring the aluminum casting. To fix this the part needs to be surface ground to a 8 microinch finish. I'll bring the part to a local vendor, Garden State Precision, who has the equipment and expertise necessary to do the job properly. I'll drop it off in a day or 2 and since this is not a rush pick it up in a week or 2.

While I am at GSP they will also do another small grinding job, thinning the crescent-shaped crankshaft thrust bearings.

The crank bearings are from a ZX10R. The journal bearings are to be used unmodified but the thrust bearing is slightly too thick to fit into my crank design. Instead of having a full-on special made, which is expensive and time consuming, I will have these stock bearings ground from the backside to the appropriate thickness. Inexpensive and just as effective. I'll have them grind matched sets in .0005 increments to allow me to dial in the desired crankshaft end float.

Coming up is the crankshaft rod journal machining. Hopefully in a few days but you know how it goes!

Until next time,

Chris

It's déjà vu all over again

2010-11-22T22:40:00.000-05:00

Seems like we were here a couple of months ago!

Once all the programming and fixturing is done making multiples is fast! That's the beauty of sand casting and CNC. Minimal material removal yet still a complex multifunctional part for a reasonable cost. The first operation on the 3 new parts ran smoothly. The crankshaft blanks nests nicely in the journal area.

Now I have to tear down the mill setup and reinstall the trunnion, dial it in, and run the remaining 4 axis programs. If those run with no problems the two upper crankcase parts will be sent off to Millennium Plating for NSC plating and honing. I'll send the J&E pistons with the castings so that Millennium can mic the actual pistons and get the piston to wall clearance dead accurate.

One task before plating is to finish machine and surface grind the stainless steel torque plate. This will be bolted to each individual cylinder bank to simulate the head clamping forces during the final honing process.

When an engine is final assembled and you tighten the head bolts the cylinder walls distort slightly from round. This is bad for piston ring seal so a the use of a torque plate simulates the distortion of clamping so that the cylinder wall is honed to a round shape in a condition close to actual running conditions.

That's all for now. Hopefully I'll have the balance of the machining done sometime this week.

Final Casting Stretch

2010-11-19T23:43:00.000-05:00

First off, apologies for the extended delay between posts. This is a project that requires a lot of time which is not always available when trying to run a one man business in a recession! In addition to client work that takes me away from time that could be better spent on this project I did manage to squeeze in a vacation riding dirt bikes in Moab, UT. It was an absolute blast and a needed recharge away from the city.

As with everything these days some of the guys in on the trip did a blog site on it at ADV rider forums, appropriately titled 'Manhattan to Moab or City Blocks to Slickrocks'. We got to ride some amazing terrain that is the antithesis of what I normally ride. Grip levels on the rock were insane and the Slick Rock trail was like the biggest skateboard park in history. The pics tell the story well.

Now on to more asphalt-based endeavors........

I received the final revision on the castings from Harmony. This 1 lower and 2 uppers should be able to be used as parts for the first engine build. The castings sown in the previous posts were casting samples that needed inspection windows and other machining features to allow verification of the internal features that precluded their use in a running engine assembly. Now that the molds have been proven out and revised as necessary these parts should be the cases of engine serial number 000001 and the top of 00002.

The overall finish on the parts look excellent and soon more aluminum chips will fly. Then its on to more crankshaft and primary drive gear machining then more parts then some more......

That's it for now. Hopefully have another update soon,

Parts is parts

2010-09-27T17:04:00.000-04:00

Just posting a few shots of the various parts that are accumulating. It's nice to start a project like this and have spare parts available to experiment with. Previous bike and engine projects have been one-offs and that presents a problem when failure is encountered- the need to wait for a replacement custom part, usually the weekend before a race! Now we'll have the ability to have 2 complete engines plus a host of spare parts. What luxury!

Most of the parts are produced to my specifications by the indicated vendor, the rest are standard aftermarket performance parts. Thanks to Barry from Celtic Racing for referring us to Skip Dowling of Orient Express, a great source for all things OEM and aftermarket in the SportBike world. Skip was able to get us the parts we need at very reasonable prices. A shout also goes out to Fred Renz of Yoyodyne, a great resource for hard to get exotic parts and just about anything Brembo manufacturers, even the true GP equipment.

Castings: a lot has been said about these parts and the great job Harmony/TPI is doing so I'll leave it at that.

Chassis Castings: great parts from Harmony/TPI here too.

J&E Pistons: producer of top quality pistons for motorsports. These are a high compression version of their ZX6-R product.

Carrillo connecting rods: What is there to say? If you want the best rod, you buy a Carrillo.

Oil pump gerotor and custom drive gears: fron Melling and SDP-SI, respectively.

Tungsten crank counterweights: From Midwest Tungsten Service. These bolt on counterweights that nest inside the con rod I beam area help keep crank and overall engine cases as narrow as possible.

Brembo front brake calipers and master cylinder from Yoyodyne: Again, if you want the best, you get Brembo.

Ohlins TTX front damper from Motorsports Spares, who usually deal with 4 wheel vehicles, but had the knowledge of the generic Ohlins components to help us source a suitable solution for our front spring/damping needs.

Cometic gaskets:

Lots of misc bolts, seals, bearings, etc.

More misc parts, mostly from Orient Express:

I'm starting to amass quite a collection of parts. Soon this chaotic jumble of parts will defy entropy and assemble into an organized machine capable of scorching the track.

That's all for now.

Flip-Flopping the Crankshaft

2010-09-27T15:57:00.002-04:00

We've made good progress on the crank so far, one aluminum test part and 3 final steel parts all have the first lathe operation complete with no crashes, broken tools, or other mishaps.

Now we remove the 3 jaw chuck front he lathe and replace it with a 16C collet nose. The collet nose will allow us to hold the part very accurately from a previously machined feature. We'll then indicate the length of the part and run the second lathe operation. This operation creates the features for the generator main bearing journal, the front bank cam drive, and the tapered stator mount.

3 jaw chuck in first lathe operation:

16C collet nose for second operation:

Now just a few button presses and the 2nd operation is finished:

Repeatedly running the program finishes out the parts for now:

Now we are finished with the lathe work. Next up will be putting the parts in the 4th axis on the mill and creating the 2 sets of offset throws for the connecting rods and the sprocket teeth for the cam chain drives. once those features are complete I'll put the part up on a manual mill and drill and deburr the main and rod bearing oil holes. Unfortunately, that will need to wait a week or so for some client work on the mill to be finished.

I Love CNC

2010-09-25T13:46:00.001-04:00

The wonders of modern technology.

From:

To this:

In a couple of hours. All the parts are accurate to within a few ten thousandths of an inch.

The switch from the 2024 aluminum test material to the 4340 steel part material required slowing the cutting speed by approximately 50% and increasing the feed rate by 25%. It may seem counter intuitive to increase the feed rate for a stronger material but the carbide insert's cutting edge needs to be able to get a decent bite into the material, otherwise it just deflects the workpiece and rubs, causing a lot of heat buildup and usually insert/tool failure which leads to a scrapped part.

Now that all 3 initial pieces are machined I will change the setup in the lathe to flip the part around and accurately hold it by the features we just machined. That post will be up soon.

Machining Step 1 on the Lathe

2010-09-22T12:48:00.001-04:00

After a couple of long days and late nights machining non-motorcycle parts the lathe is open and I can run a test part of the first crankshaft program! I'm making the first part from some scrap 2024 aluminum to verify the program before using the more expensive and much harder to machine 4340 steel material.

The machining process will be:

drill 60 degree center in outer end for tailstock support
roughing the main profile
finishing the main profile
machining small undercuts on main profile
machine center main bearing fearure
remove as much conrod journal stock as possible

This is what the setup in the lathe looks like. As with the engine castings, we are at the limit of machine capacity but the part fits and that's all that matters.

This is taken after the finishing of the main profile:

And this is taken after the program is complete:

Here's some CAD vs reality for a comparison:

The aluminum version looks nice but would never be able to withstand the temperature and stress of operation. Next up is the 2nd machining operation that finishes the opposite end main bearing and tapered generator mount. After that operation the part will move to the mill for some 4 axis work on the conrod journals and camdrive sprocket teeth.

Until the next update......

Programming Setup 1 on the Lathe

2010-09-20T20:48:00.000-04:00

The first step in converting CAD to chips is to plan ahead, and it should happen very early in the design stages, otherwise you run the risk of having an unmachinable or hard to machine part. What we are doing here is step 2, converting 3D CAD to 2D CAD to G-code CAM. The 3D CAD provides complete surface information of the part. Since at this stage the part is a simple revolved shape, we can reduce it to a 2D profile and not lose any information about the shape. From this 2D profile the CAM software creates a series of 2 dimensional moves along the X axis (diameter) and Z axis (length of part) that create the part profile from solid bar using appropriate cutting speeds and feeds.

3D CAD:

2D CAD:

2D CAM:

Now we can go to the machine, which is currently busy.....

The CAM package is told the shape and position of the various tools needed to cut the part, it is told the shape of the part, and it is told the characteristics of the machine. Doing what computers do well, crunch numbers, it uses all of this hopefully accurate information to calculate the appropriate motions to generate the desired part profile. As with all computer programs, garbage in=garbage out, except instead of the BSOD or an inaccurate spreadsheet, you get twisted metal and a large repair bill. It is a very good incentive to make sure all the info input is correct and also carefully check the output. The output of this 2D CAM process is a text file in what machinists call a G-code format. A sample g-code file in a format usable by my Siemens control looks like this:

%MPF52
G70 G90 G40 G54
(TOP-CAP-3-rec2-rad PR=3.745 Z1=8.075 )
(T-2 O-6)
(DCGX IN SDJCR-123)
T02 D06
G0 X0.825 Z.5
Z0.
M3 S1000
G96 S1000
M8
G1 X-0.0357 F.005
G0 X0.6316 Z.155
G96 S1500
G1 Z-2.99 F.008
X0.6864
G0 Z.11
X0.5567
G1 Z-2.4417
X0.5625 Z-2.4475
G3 X0.57 Z-2.4656 B.0256
G1 Z-2.99

The format is relatively simple and once you have used it a bit reading it is pretty straightforward. The G-Code file is sent to the machine over the network and then after machine setup the program is run.

Once my current lathe job is complete the crank goes right in. I hope to have another blog update sometime this week.

Starting on the Crankshaft

2010-09-19T23:03:00.005-04:00

Now that the engine case patterns are approved and the production order placed I can move on to the crankshaft.

It will be a 180 crank to exploit the reduced variations in reflected crankshaft inertia that this configuration provides, similar to Yamaha's cross plane crank in the M1 Grand Prix bike and the R1 Super Bike.

I will be initially testing 2 different versions of the crank- one with pork chop counterweights and one with full circle counterweights. The main testing variable is the overall weight/inertia vs. aerodynamic efficiency of the 2 versions.

Full circle configuration:
Pork Chop configuration:

The manufacturing process will be as follows:

Material blank:

3 3/4" diameter x 9.7" long
4340 steel
28-32 Rockwell C hardness

In house:

Machine crank on lathe in 2 steps blank leaving .01-.02 stock on surfaces to be ground.
Mount lathe blank in mill 4th axis and rough machine crank throws
Rough and finish machine the two silent chain cam drive sprockets with custom form end mill cutters.

Outsource:

Hobbing of primary drive gear and starter clutch/crank sensor spline will be done by Eagle Machine, Inc. of British Columbia. They have experience to properly deail with custom low production crankshaft.
Final Grinding of main and rod bearing surfaces will be done by Lopez Crank Shaft of Santa Fe, CA. They are another custom crank specialist and can provide the accuracy and surface finish needed.
Plasma nitriding will be done by Accurate Ion Technologies, a specialist in steel hardening and advanced surface finishes. We are using plasma nitriding for it's low process temperature that enables proper multilayer surface hardening of the part with no distortion.
Once we get the part back from Accurate Ion it is ready for use.

The process will involve 2 lathe setups and one milling setup.

The lathe first lathe setup will hold a 3 3/4" x 9.5" long material blank in a 3 jaw chuck. we'll machine one end of the crank, the middle main bearing journal, and various smaller features on one end of the part.

End of first lathe setup:

Once I finish some client lathe work currently running this is next in line. The next post will detail programming and cutting of this first lathe operation.

Long Block Assembly Shots

2010-09-16T20:31:00.005-04:00

Now that we have a girdle, top, and a couple of heads the time is ripe for some assembly shots. I'll let the images speak for themselves...

Short Block:

Long block:

The overall engine assembly is very short front to rear to enable a long swingarm in a short wheelbase. The resultant slight additional height compared to a normal I4 is easily accommodated by the unique chassis needed for the Hossack-style front suspension.

Finishing the Girdle Machining

2010-09-07T20:01:00.026-04:00

This blog post is dedicated to Chris Hodgson from San Jose BMW. I saw Chris and his crew at the BUB Bonneville motorcycle speed trial event last week while helping wrench for Scott Kolb on his 125cc partial streamliner. Scott set a new 2 way record of 146.7mph on the last day of the event after lots of tweaking. There's an article over at Hell For Leather on the effort. The trip was lots of fun, especially when a record is set. Every speed lover needs to go to Bonneville. It's only 2 hrs outside of Salt Lake City and besides having no speed limit also presents an awesome vista in any direction.

Back to the topic at hand, I had the short block with me for display purposes and Chris Hodgson was like 'when did you do that machining, the blog is not up to date, what are you waiting for!!!!!' Being chastised by an internet follower compelled me to get my ass back in gear. That fact that it was a person who is a world renowned BMW tuner made it go into high gear! Chris and crew also took a record with their BMW HP2 so it was a happy pit area all around.

Chris, this update is for you and hopefully I will be able to work on the project and update the blog regularly.

Now on to our regular programming...........

After the last post, which was machining the girdle split surface, we are up to the balance of machining on the girdle part. We were up to this point on the part:

Oil gasket and split surface machined:

The next step is to machine the girdle subplate then complete the part machining. The subplate screws to the oil pan surface and is accurately aligned to the trunnion table with dowel pins.

The first set of features to be machined is the crankshaft main bearing split surface:

Facing:

Drilling/tapping.......

Then the 4th axis is indexed 90 degrees and the clutch side is machined. there is a bunch of profiling for the cassette transmission side plate, trans and oil shaft bearing bores, gear clearance, and misc threaded holes.

Cassette mounting flange:

Gear clearance:

Roughing the bearing bores:

Once these deep bores and pockets are done the 4th gets rotated -180 degrees to machine the output sprocket side. The features on this side are the generator cover surface, oil filter mount, oil pump drive and pressure chambers, and starter bore. Yes, a starter motor! No rollers, no bumping, just press the magic button.

Facing gasket surfaces:

Some operations are pushing the limit of tool stability, like this 1" dia x 8" long insert end mill:

Starter motor mounting hole:

Gerotor porting:

The oil pump is a gerotor supplied by Melling, a high quality OEM/aftermarket automotive parts manufacturer. This style pump is highly efficient and compact when properly packaged. A lot of design assistance for the entire oil pump circuit was provided by Marc Goulet of Melling. Marc is also a motorcyclist and was kind enough to donate his time and put up with my unending questions on the subtle details of high performance oil system design. Marc has been involved in the design of some top level F1 engine oiling systems so he is definitely the person to ask in this field.

Inner and outer oil pump gerotor:

These parts fit into dual eccentric pockets that have CNC porting designed to allow high flow with minimal power losses.

Those 3 machining positions contain all of the high tolerance operations. Now on to some less critical ones:

Oil drain hole:

The position of the subplate is then indexed 90 degrees on the trunnion table and we machine the:

Upper engine mount:

Lower engine mount:

Starter mount:

That covers the majority of the machining on the girdle. Bearing bores will be finish machined as part of a complete crankcase assembly.

It ends up being one sweet looking part:

Stay tuned for more soon!

Machining the Gasket Split Surface

2010-07-02T22:21:00.004-04:00

Now that we've gotten accurate mounting features and a matching fixture plate we can start machining the rest of the part.

These operations are relatively simple, some facing, drilling and a bit of spot-facing. I'll be machining the following features:

face the main gasket surface

drill/main bearing stud holes

drill/tap crankcase attachment bolt holes
drill cylinder head oil drain holes
spotface/drill oil passage in filter area

That's all I have for now. I hope everybody has a fun 4th of July holiday. Until next time.

Chris

Machining the Girdle

2010-07-02T21:00:00.005-04:00

Now that the girdle has been scanned and determined to be accurate, I can reference known location features to accurately position and clamp the part to the mill bed.

Once rigidly clamped onto the bed, chips will start to fly.

Literally.

machine fixture plate and mount part

Now we're ready to machine the rest of the features using the 4th axis setup. Unfortunately, it's time to shift to some customer work for a few days.

QC on the Crankcase Girdle

2010-06-21T21:53:00.015-04:00

The sample casting for the crankcase lower section just came in. This part contains the crankshaft lower bearing caps, oil pump/filter and drive system, and the transmission and clutch. Although it looks visually more complicated than the crankcase top, it is a simpler piece to cast in that there is only one internal passages requiring a buried core, namely for the oil pump pressure area.

The placement of this core is less critical than those for the cylinder bores because of the lower pressure and thermal stresses this area experiences. This core forms the pump inlet and outlet ports, high pressure chamber, pressure relief valve port, and oil filter mounting boss details all in one piece. One of the benefits of the casting process is that part complexity is not penalized as it is with billet parts.

The QC process used on this part will be the same as for the crankcase top:

scan

overlay to CAD to verify fidelity to the CAD model.

This sample part was dimensionally excellent. There are a couple of areas I may modify after going through the part's CNC programming process. I'll know more as the part moves through the various machining stages.

That's all for now.

Chris

Part 2-Machining the Crankcase Top

2010-06-14T17:22:00.019-04:00

Now that the crankshaft split surface and related features are machined the rest of the machining process for the part is easier. If all of the previous scanning, QC and OP1 processes went correctly then this stage should be a breeze. Hopefully I don't regret that statement!

We are starting here, a part located on the fixture plate with the majority of machine work yet to be done.

The next machining steps are as follows:

machine the generator side features: gasket surface, mounting holes, and main galley oil passages, and logo cleanup

machine clutch side features: gasket surface, mounting holes

The logo on this side was left as-cast to see which looks better. I prefer the milled one.

The part then gets rotated 90 degrees for the following operations:

Bank1:

Face deck surface with 6" face mill. The 6" diameter tool machines the deck surface with one sweep, crating a very flat and consistent surface.

Rough mill cylinder bores. I use a long 3/4" diameter 6" long 3 flute carbide end mill held in a milling chuck, both from Mari Tool, for maximum rigidity. The cut was deep but clean with no chatter. It was a good enough finish to send directly to the platers but I wanted the extremely straight bore that a finish pass with a boring head would provide.

Cleanup coolant port passages. This was step one in showing how well the internal coolant ports were aligned to t he core and cope of the mold. One bank had excellent alignment, one bank needed a bit of tweaking, but this is the area where we expected a large tolerance stackup. Harmony will likely revise the gauges used to place the cores to all

drill and tap cylinder head bolts and dowel holes

Finish cylinder bore to .008" oversize in preparation for nickel silicon carbide plating by Millennium Technologies. This was done using one of the single point boring bars from Microbore with a TCGT ground and polished carbide insert.

Then repeat the same operations for Bank 2.

Valley:

coolant ports gasket surface milling
coolant port mounting holes drill and tap
oil pressure sensor drill and tap

So far so good. No crashes, although I did nearly break a couple of tools from unforeseen interference between the trunnion tailstock and the long tools installed in the toolchange umbrella.

In general the entire machining process was fault-free. The stiffness of the trunnion from Martin Mfg. was excellent. The large tools cut as if the part was clamped directly to the machine table, no ringing, chatter, or other abnormal tool behavior. The bore finish from the Microbore boring bars is better than expected.

Once the casting patterns have some slight revisions done they'll run 5 more parts that will then get machined.

I am very satisfied with the results so far. The sample casting for the girdle part just arrived, so now I can start directly on that and hopefully have just as good a time.

That's all for now.

Chris

Machining the Crankcase Top

2010-06-11T18:10:00.011-04:00

Well, I finally got some time to get into the crankcase top sample casting. This post documents the first operation on the part. The QC results were mostly positive, there were only a couple of minor issues with the initial test pour which will be revised for the next run of parts. For a casting with multiple internal cores of this complexity I am very happy that the issues that were found were minor and easily corrected.

The first machining step is to clamp the casting upside down onto the mill table and align it with the machine X and Y axes. it is important to design features into the casting that will allow easy and repeatable initial positioning. This step was pretty easy as I already had a good idea on how accurate the casting was because of the previous QC scanning procedure. The 3 main datum points that define the XY plane and create the crankcase split plane were very accurate and enabled easy and stable clamping. Then 2 additional points to locate the x-axis orientation then one more point to locate the origin. 6 location points perfectly constrain 6 degrees of freedom and now the part is ready to go. Sorry about the crappy image but I started machining before I realized that no pictures were taken of the setup and had to grab this from a video.

Once the part was aligned I setup all the tools in the carousel and triple checked the program, then started making chips.

Machining o-ring oil seal grooves....

Drilling/tapping main bearing and case attachment holes.....

Done with operation 1!

After op1, I needed to make a fixture plate that matches the pattern of tapped holes I just machined into the part.

AutoCAD sufficed for this.....

The part clamped to the fixture plate.....

which is then clamped very accurately to the Jergens fixture pins built into the trunnion table.....

From here I will need to run 2 more programs, one for the each cylinder bank- decking it, oil and head bolt holes, etc, and the second for the side cover mounting faces and attachment holes.

I'll get to this soon and put up a post as soon as I do.

That's all for now.

Chris

QC on the Crankcase Casting Top

2010-05-24T14:43:00.017-04:00

I received the crankcase casting top sample piece on Friday and got right down to seeing if it was within specification to the CAD model we used as a master. Overall the part looked very clean with all features well formed and no visible pitting or porosity, so it was a great pouring job by the guys at Harmony.I proceeded to setup a scanning station that would give good access and a stable platform to scan the part.

My approcach was to use the scanning arm to locate major planes of interest: cylinder deck, bearing split surface, and large external surfaces, then some cylinder primatives of bearing and cylinder bores, then create 3d profiles of more complex surface intersections.

The result of this was a relatively confusing collection of surfaces, points, and lines randomly oriented on 3D space.

The next step is to make sense of all this data by aligning it to the CAD model it is supposed to accurately represent. First we align it to the CAD model that has extra machining stock on the appropriate areas:

After a careful alignment process the scanned data seemed to closely match the CAD model on all external areas. To ensure that my addition of machining stock was correct I then replaced the as-cast CAD model with a finish machined CAD model:

What I look for in this step is a gap (at least .030") between the scanned surface and the final machined surface, which indicates there is enough material to cleanly machine the surface.

So far the casting is well within specification, an excellent job by the casters considering the multiple stackup of cores and tolerances. I need to do a couple of more scans to capture the bottom/inside of the part and do a similar analysis. Then the part goes on to the mill, gets finish machined, then the deck gets milled out to examine the interior water passage core placement which has a large influence on will the cylinder wall thickness consistency.

Hopefully I'll be machining this week and have some more images and video of the process.

Chris

No Drips Around Here

2010-05-20T15:51:00.006-04:00

I received a package of custom gaskets from Cometic today. They are the largest gasket maker in the country, supplying both OEM and aftermarket manufacturers in a variety of industries. They were really easy to work with on getting several engine case and oil pan gaskets cut from their bonded rubber AFM material and on having MLS head gaskets made from a modified version of a ZX6R part.

The clutch cover, generator cover, and oil pan gaskets are made from a chemically blown compounded nitrile synthetic rubber that is bonded to an aluminum core so they have a bit of strength and won't just rip like paper gaskets. The process was simple, I grabbed an outline of the appropriate surfaces from my CAD model of the engine, saved them as DXF files, and emailed them. A couple of weeks later- custom gaskets for a very reasonable cost. Cool stuff.

They can do the same for just about any sealing surface so if you have an old car, tractor, vintage bike, etc. that is hard to find gaskets for just give Mike Sauer at Cometic a call.

Head gaskets are not as simple a part as an engine cover gasket. They need to withstand high temperature and pressure loads cycling at a rate of over 200 times per second. For this reason I did not want to start from scratch and preferred to modify an existing Cometic part. They were able to modify one of their .018" thick Multi Layer Steel head gaskets to add material where needed and then trimmed the overall length to size.

Overall all the parts were within tolerances, so one more item completed on the road to a running engine.

That's all for now.

Chris

The Eagle Has Landed, with video.....

2010-05-18T19:52:00.006-04:00

Or the trunnion table has been mounted on the mill. Spent the better part of a day cleaning and mounting and aligning the table properly then a lot of productive time turning the jog wheel back and forth watching the table tilt. Much more fun than watching paint dry.

Here's a short video sequence showing 1, 2, 3, and 4 axes of simultaneous movement. Many machines are really 3.5 axis which means the X, Y, and Z axes can move or the 4th axis can move, but not all at the same time. This machine is a full 4 axis machine. The last move shows the X, Y, Z, and U axis in a synchronized movement.

This added capability enables making complicated and high tolerance parts with a minimal amount of re-clamping operations but is also possible to quickly damage the part, tooling, and machine with any incorrectly programmed move.

The next steps this week are to get the suspension spider fixture plate mounted and machined then make a sample part. I'll tackle this part first as it is pretty simple compared to the engine castings.

Chris

Tooling Board Pictures

2010-05-18T13:45:00.003-04:00

Harmony/TPI just sent me some full shots of the pattern used for the front suspension spider and clip-on mount. They are interesting to see- besides the part geometry there are riders and sprues, both of which are much larger than I would expect.

The suspension spider pattern:

The clip-on mount:

The patterns are made from Renshape, a tooling board material that is easy to machine with a good surface finish. The pattern material is protected from the abrasive casting sand by the thin plastic film draped over it. I like the fact that the film has dual purposes: to improve the surface finish of the cast part and to increase the lifespan of the tooling used to make that part.

After a bit of necessary contract work to pay the bills I'm now in the final stages of mounting and aligning the trunnion table. A post will follow shortly.

Chris

CRANKCASE PHOTOS!!!!!!!!!

2010-05-13T15:44:00.007-04:00

I just got a great email from Harmony Castings showing some images of the first pour of the crankcase top casting.

This is the first sample and is now being x-rayed to check for porosity. Once it passes muster for that it will be sent to me.

I'll scan the part using a Romer Arm to make sure the exterior surfaces are within the tolerance range of the CAD model.

If the exterior surfaces are all within spec the next step will be to cut off both deck surfaces to check coolant passages for any signs of core shifting. Unfortunately, this will make the part unusable for anything but a machining test part.

I should get the part next week and start the process. The crankcase lower will be poured sometime next week and then i get to repeat the process.

Until then.

Chris.

Boring Bars Have Arrived

2010-05-07T12:36:00.007-04:00

I came in this morning and saw a nice package by the door with a UK return address- the boring bars!

These tools are used for finish machining the many accurate bores needed in the crankcases- transmission bearings, crankshaft journals, and cylinder bores. Because many of the bores are deeply recessed in the casting I felt a normal extended boring bar would not be able to achieve the required accuracy and surface finish.

The tools are from Microbore, a custom tooling house in the United Kingdom. I wanted to use domestic US suppliers for as much of this project as possible but all of the US tooling vendors I sent a RFQ to declined to quote the project. Microbore has done similar products in the past and their high quality, experience and reasonable pricing easily convinced me to choose them.
The boring bars are of the Devlieg adjustable insert style with an integral CAT40 shank. This will maximize accuracy and rigidity versus a boring bar held in a collet or end mill style holder.

Each bar has an angled machined pocket at the extreme end that receives a Devlieg Micro-Adjust carbide insert holder.

These Devlieg insert holders allow fine diameter cutting adjustment using the latest carbide insert cutting edges. We will use a test part to dial the cutting diameter to size for each bore then lock them in place.

In the next week or so we'll be machining the first castings and post some video and images of the results.

That's all for now.

Chris

Lee Klancher Article in MPN

2010-05-03T15:10:00.004-04:00

Thanks yet again to Lee Klancher I am getting some press exposure in this month's print and online issue of Motorcycle Product News. The online edition is here.

Lee got in touch with me about a couple of years ago and asked to take some pictures of our shop for his upcoming book, 'Motorcycle Dream Garages' It's a great collection of real world spaces with grit under their fingernails. Little did I expect to get an entire chapter to myself and one for my neighbors at Spannerland! The book is quality, from the large pictures and great text to the print quality and binding.

Like most people, Lee was interested in the upcoming V4 project when he heard and saw what we are up to. Unlike most people, Lee is a journalist and saw the chance to help get a good story out. We've been in continued contact and articles such as this are the result. As the project progresses we can expect to see more.

I'll be getting to machining some castings this week and will post some images and video once it is sorted.

That's all for now.

Trunnion table Has Arrived

2010-04-02T15:31:00.010-04:00

Today the trunnion table for our 4 axis machining center came in. It is a custom design from Martin Manufacturing Services and is a beautiful piece of work. It will be used by us for accurately and quickly machining many parts, most importantly the crankcases, but also some suspension castings and the swingarm for post-heat treat machining.

Stan from MMS was receptive to making a design to my specifications and delivered exactly what I needed. He is also a big MotoGP fan hoping for a good showing from Spies, as we all are! It was nice to talk with a vendor that shares some common interests, especially another person who felt bummed out about the direction Moto2 took with the spec engine! Once he heard this was for a custom racing motorcycle project it really piqued his interest. Regardless of the application, he did all he can to provide me with the best product at an extremely reasonable price.

The surface of the table has features to locate a Kurt vice and a square pattern of Ballock locating/clamping pins that for use with a fixture plate that will allow me to index the parts 90 degrees with an accuracy of +/- .0005". He supplied 3 ready to use fixture plates made from Mic6 cast tooling plate.

Having everything in 3D CAD enables me to simulate machining operations and verify clearance and machine travels.

Many of the machining operations will be done using by custom boring bars from Microbore which should be here in a couple of weeks.

Programming of the parts is nearly done, once the boring bars are in all we will need are some castings and then the chips will start to fly.

Until the next update,

Chris

Project Overview

2010-03-31T18:33:00.006-04:00

I just realized there's no info on what we are building on this blog. You can find more info at www.moto2-usa.com, a URL name whose significance is largely irrelevant to our efforts at this point, but here's a primer. Hopefully saner minds will prevail and they will open up the specification to more engine configurations in the future.

Anyway, we started this project after seeing the FIM release with the initial Moto2 rules.

Here's a good analysis of them by David Emmett of motomatters.com

This quickly changed to a Honda spec engine which dashed our hopes. Ever the outsiders we decided to continue on and build our dream bike, which does not include any part of a CBR600. Now we have finished with the design and are starting fabrication of the following bike:

The chassis and suspension designs have been race tested over the past 7 years with good success. This bike is taking all we learned and incorporating a custom designed V4 engine as a powerplant. As soon as we have a rolling chassis we will be doing development, internally at first, then partnering with Celtic Racing, a top AMA race team, with access to top rated national riders, as the bike comes up to speed. We'll enter a few local club races by the end of the season and see how the bike does in competition.