NJMP Race Report

Wow, I have not written a race report in a long time and longer still since it was me riding!  Nice to break that streak.  Its also a long time since Mom was able to visit.  I think she brought some of the good luck we had.

One of the things I forgot in that time period is all the effort a roadrace weekend takes.  While I had leathers and boots, the rest of my safety equipment was shredded or missing.  I called a few friends and ended up with a set of Jerez gloves and a summer undersuit from Will and Gus at Rev-It USA.  The gloves were great and the summer undersuit make moving around while in my leathers much easier.  It is not mentioned much but you need to be pretty flexible when racing smaller bikes.  You really crawl all over the bike through the various phases of acceleration, cornering and braking, and the smoother it can be done the better.  Having leathers grab at your sweaty skin while transitioning from side to side does not help that  much.  It also makes getting out of leathers much less like a spastic dance.  I also got a new Bell RS-1 helmet from Chris at Union Garage.  Race organizations want the latest agency approvals and my helmet was too old to pass.  I've been an Arai guy for most of my roadracing time but before that I wore a Bell when MXing as a kid.  Seeing them getting back into pavement stuff and some childhood reminiscing (and a great fit) was enough to make a change back.  Chris was a big help and got me the helmet in time for the weekend.

Overall, I have not had many better weekends at the track.  The first amazing part is I never took the engine out of the frame but that is jumping ahead of the game.

I shared in a van rental with friends of a friend, Lex and Alex, who were also heading down.  They showed up with one nice Ducati and....... not much else!  Really, not much else at all.  I wondered what they thought about me with my one small bike.  And toolbox.  And spares box.  And spare tires and rims.  And tire warmers.  And remote starter.  And cans of race gas.  I guess that's the difference between store bought and home rolled!  Anyway, it all fit and off we were.

Getting to the track Thursday night after a 2hr drive was also a welcome change.  I'm used to LRRS, Summit Point, and VIR, which are 6, 5, and 9 hr drives respectively.  2 hrs is just getting warmed up!  I also shared an above-garage apartment with Jamie Waters, part of the original Spannerland crew and Norton collector extraordinaire.  Jamie brought 3 bikes.  When some people crash or break a bike they fix it.  Jamie switches bikes!  Just kidding, they all ran well as did the rider.

I had to take the Friday school to renew my license since it has been 3 years since racing.  Damn, its been too long!  This was a smart move anyway since I was extremely rusty.   I guess my brain likes to keep it out of consideration but I have not ridden a motorcycle since my Duke was stolen nearly 1 year ago.  It has been too long.  Anyway, going from not riding to a racetrack is a bit much so the slow pace of the school was a nice welcome back.  The AHRMA school was nice, even though they made me wear the bright orange vest!

The bike ran great all day, helped by my slow pace not taxing anything but my out of practice brain and body.  I had my pre-season testing paint scheme in place.

Friday went smoothly so I was expecting some tantrum on Saturday.  I was only mildly disappointed in this.  I had some family and friends there for both days so was hoping for at least a decent showing.  Saturday practice was only one session which went well.  After that I had a new set of tires put on for the race.  A new set of slicks.  I did have a set of rains (I thought) but not installed, but no worries, its sunny!

Famous last words.  As race 7 got close the sky darkened and some drops started to fall.

In a span of 20 minutes we went from sunny to rainy.  I suited up and asked Scott to go have Miles at Street and Comp do a quick tire swap.  When he came back without tires it was not good: turns out I brought 2 front rains and no rear so rains were a no for this race.  As I was hoping the rain would stop, it started coming down harder.  With a bunch of people having come down to watch me I had to go out with my new unscrubbed slicks when 3rd call was made.

Worst case I would crash.  2nd worst case, I pull in and feel stupid.  I never expected to have a best case to consider!

Due to my late entry I was gridded pretty far back.

When the flag dropped I proceeded to spin the rear tire and almost drive off into the grass.  Not the best move but I didn't dump it yet!  I recovered, wiped off my faceshield and started to tiptoe around the track.  The rain only got worse but I started to get into a groove.  Not a smooth groove, but a slipping, sliding, moving all around groove.  It was enough to bring a little of my confidence back.  Little by little I started going faster.  Every now and then I passed someone.

Then I passed a few someones.  Then I had some clear track and made some good progress in working the rust out of my riding.

I was having a bit of fun.  Due to the rain and the slick tires I could spin the rear at will.  OK, I was having a lot of fun!  What I didn't know was that all my friends were on top of the scoring tower and could see me around the entire track and I was putting on a pretty good show!  About 2/3 of the way throgh the race the bike start coughing and spitting a lot.  They could hear it on the tower.  Thinking some water got in the electronics I was hoping to just nurse it home.  The only problem was that it ran best when wide open so that's what I had to do.  That's when the weirdest thing happened.  2 bikes came past me and it turns out they were the leaders of the twins class (which started in the first wave, I started in the 2nd wave) and they were lapping me.  They lapped me so I only had to do a 7 lap race, not 8!  The bike couldn't die on the last lap because this was my last lap!  I don' think anyone has ever been happy being lapped until today.  Talk about making lemonade when the world gives you lemons!

Anyway, coming thought turn 1 dead last I had no idea of my finishing place in the race.  After a few minutes they posted the results and we found out I won my class!  I think it was also 3rd overall which means I did a lot of passing!  I really felt on top of the world, even if it was only a small club-racing world.  I've had a lot of lows while racing and sometimes forget how high the highs can bring you emotionally.  It is nice.

Anyway, no rest for the weary: I was also race 9 which means we had 10 min to swap out the tires for new rains that Scott had put on my spare rims.  It was a scrambling scene from the old days but with some new characters!  I had my brother, Uncle John, and cousin Johnny swapping rims and brake rotors while my mom and sister tore the tailsection off to dry and cover the electronics.  I'm really disappointed we didn't get a picture of this.  I guess they were all busy!  They were a great pit crew and as everything was tightened up we heard 3rd call. They finished just in time!  No worries, now just start the bike and I'm off.

Except I couldn't get the bike started.  It turns out that the battery on the external starter I use was a bit low and couldn't then the engine over.  It is one of those heat of the moment things that I could not think clearly and resolve the issue so missed the race.  I was not too bummed as this race was against all twins so was not something I would be competitive in anyway.

In the aftermath of thinking the engine was broke I found what caused the rough running in the main race.  Turns out the throttle body had popped off the rubber intake manifold and was bouncing around under the tank.  There is not much room for it to go anywhere but at part throttle the lower fuel injector was likely squirting into the airbox, not the intake port.  When I opened the throttle all the way the fueling switched to the shower injector which did point into the intake port.  Mystery solved and NO BROKEN ENGINE PARTS!!!!  Simply amazing.

After fixing that and zipping the rest of the bike back together we were ready for Sunday.  A dry Sunday, which is nice for the spectators, as I had another group come in, some friends with their kids, all of which had a great time.  They particularly like the stunt show.

Sunday's race was nice and sunny and almost hot.  A nice change from Saturday.

I had a similarly bad start and did start to pick a lot of riders off but couldn't pull off Saturday's result again.  I ended up 3rd place, not too bad, with the lead group in sight ahead of me.  All my race laps were faster than the previous so that is another positive to take away.

At the end of the day I was not sure how to feel.  I finished the races that counted, didn't crash and the bike still ran!  Was I still me?  A nice dinner with the Sunday pit crew was the perfect ending to the day:

Well, that was a great weekend.  Hopefully I'll be able to do another sometime soon.  Barber in Oct maybe?  Who knows....

The best flag ever

Is always the chekered one!  Had a ball this weekend at NJMP and will do a proper race report this week but now I need to pay some serious attention to some clients that have been neglected.

YES!!!!!!!!!!!

A needed distraction

I did mention this a few months ago but have not posted again being in fear of the universe getting too much of an advance notice of my plans and throwing a wrench in the works.

I'm making a long needed return to the racetrack this weekend at the AHRMA event at New Jersey Motorsports Park.  I'll be riding the Rotacular, something I have not done for almost 5 years.  I don't think I ever raced the bike (Todd Puckett was my rider) with the Ducati head and fuel injection so hopefully it will be a great weekend rolling on the throttle.  Of course there is a strong possibility that it will be a long weekend rebuilding the engine but what the hell.

If anyone is in the area it will be a great time with lots of really cool vintage machinery and a bunch of modern stuff thrown in for good measure.  And the Rotacular.

I've spent a few days looking the bike over from a chassis perspective and everything looks nice and solid.  After getting a couple of new batteries (one for the bike one for the starter) I attempted to start the engine.

SWEET!!!!  It started on the first try and sounds as mean as ever.  That's 560cc of cylinder firing every other revolution and putting out mid-70s Hp at the rear wheel.  Tomorrow or Wednesday I'll get the bike on Peter's dyno and do a few runs under load to make sure its ready for the track.

Racing happens on Saturday and Sunday from 12-5.  I will be racing in Sound of Singles 1 (my main class) and Sound of Thunder (the twins bump class) both days or until the fuse on my engine runs out.

I'm excited.  Very excited.  And a bit nervous.  And that's good.  Can't wait until the end of the week. Its been a long time since I've been woken up to the sounds of racebikes starting.

Wish me luck!



Chris

Revelling in cast steel parts.

Parts!!!!!!!!!

There's something about getting a box of parts made using a technique that you cannot do in-house that is somewhat special.  I blast out billet parts all the time and sometimes barely pay attention to them where non-machinists are blown away.  Yet opening the box and getting these cast parts, which are much less accurate and have less bling factor than a nice billet part, was really exciting!  Maybe because it means that a rolling chassis is not too far away, maybe because it's just another cool motorcycle part, or maybe I just got up on the right side of bed today, but I'm happy.

We can see that there are an odd number of parts.  Apparently they had one investing failure during the process and that part didn't make it.  He's gone.  And there was nothing we could do.  This is normal for a first time running parts and since I was hoping to get 50% success actually getting over 80% is great.  My plan is to machine 2 sets and leave the rest as is in case there are modifications that are needed.

The shot below really shows the progression of the part from concept to production.

The leftmost shot is the swingarm area of previous designs.  There's a lot of thinking involved between steps 1 and 2!

The gold part this is where this piece goes in the overall scheme of things.


The parts have great surface finish and in the next few days I'll do some 3D scanning and 2D inspection to see where, if at all, the parts deviate from nominal.

That's all for today.




Chris

Arrgh!

The Box came in.  The box cutter came out.  The phone rang.  That was the end of my bike time for the day.  Damn.  Will resume tomorrow with a detailed examination.

Chris

And the money shot!

They just sent this over, parts are ready to ship!  Simply beautiful.  And a great shot too!

With the parts looking this good I'm tempted to give one frame a clearcoat finish.




For a change of pace I'm off to help Scott Kolb a bit on his Bonneville LSR bike this weekend.  You gotta earn the trip out to the flats!

So Close!

Just got an email from Harbor Castings with lots of pretty pictures of my parts going through the investment casting process!  There's something extra cool about seeing process pictures of your parts going through the process instead of some generic Google search images.

The wax parts I sent them looked like this:

The first step in the process is to attach the parts to a 'tree'.  The function of the tree is to create a large passageway for molten metal to fill the parts and to provide a reservoir of material to assist in keeping the molds fully filled as the metal cools and shrinks in volume.  Arranging several parts on the tree allows the foundry to make the most use of the available pour size.  These guys didn't skimp on the tree or runner sizes!  It may seem wasteful but all of the scrap can easily be recycled with minimal effort as they are a foundry.  The small red tubes are vent lines to allow gas to escape as the molds are being filled with molten metal.  The white cone at the bottom is a ceramic part that the investment bonds to and which forms the opening into which the metal is poured.  Looks like a textbook tree.

Once the parts are on the tree it is time to 'invest' them.  In production this is an automated process that repeatedly dips the tree assembly into a fine ceramic slurry and then lets dry.  The composition of this material is important as it needs to transmit fine detail yet be strong enough to survive handling and thermal shocks.  After several coats the wax parts now have a thin ceramic shell surrounding them.  The shell is still uncured 'green' ceramic so is very fragile.

As more layers as added the part becomes decidedly puffy looking.  After several layers of a fine slurry that  closely mirrors the parts surfaces and textures a couple of thicker, more coarse layers of ceramic are added to make the assembly more damage resistant.  Any damage from here on in makes the part scrap so it pays to pay attention and take care.

The tree is now ready for the next step in the process which is melting the wax out and curing the ceramic to a hard durable shell.

A steam autoclave melts the wax out and ensures that the inside of the ceramic mold is completely empty.  Note that the hollow cone that was the ceramic base of the tree now seems to be an integral part of the entire assembly.  The insides seem extremely clean, sign of a complete burn out with high quality wax.

The hollow tree is now fired in a high temperature oven to harden the ceramic.  Yes, that is really hot.

While the ceramic is still hot it is put into a sand box and molten metal is poured into the opening at the top of the tree.  A filter is placed at the opening of the tree to filter impurities from the metal from getting into the mold.  The sandbox is to slow the cooling of the mold and the metal which minimizes built in casting stresses.

 Yes, its still really hot.

Its like my own mini sun!  Now to slow cooling even more a drum is placed over the filled mold.

Once the parts cool it time to unwrap them.  The easiest method is to just shatter the ceramic off of the metal parts resulting in this stage.

Most of the outer material just falls away but the material inside the pockets requires more effort, or a vibratory tumbler, to get out.  The central sprue of the tree is now a solid block of 4130 steel that can be recycled after being cut from the parts, which is happening here.

The parts are then given a light bead blast to remove any remaining investment material and mold scale.

SWEETNESS!!!!!!

The parts look great and the smooth surface finish is a relief after all the work that went into finishing out the Makerbot mold patterns.

Now I need to find some time to put into machining both the fixtures and the parts.  Now that these have come out so well I'll start the same process for the remaining 2 parts: the lower chassis crossmember and the front suspension mount.

Slowly but surely progress is being made!

Some virtual progress

I heard back From Harbor Castings and it will be about a 2-3 week turnaround for my parts.  In the meantime the machining fixtures need to be made.  Part of the design process is having a decent understanding of how any given part will be made.

In the case of the two swingarm pivot members I knew that the part was a casting and would require a decently complex fixture to hold properly.  I knew from experience that the trunnion and baseplate technique works extremely well so would use that as a basis.  Knowing what surfaces need to be machined led to a part orientation like this:

It may seem counter-intuitive to not lay the part down but the needing access to the top and bottom of the part and the two pockets for the main frame spar tubes dictate this placement.  It allows easy positioning into these orientations for a simple contour operation to create the pockets and unrestricted access to the front and back of the part:

The next step is to put a big block of material around the part:

And cut it away with that ever-sharp unbreakable end mill of 3D CAD.  Michelangelo was on to something when he said that inside every block of material is a shape that needs to be set free.  I think he was the first machinist, among other things.

Then add in some fixture points and clamping screws and voila, a useable fixture:

The purple part is an alignment pin, the small red screws are clamping pins that hold the part, and the big red screws are structural members that close the open end of the 'U' shaped fixture.  These 2 screws add a lot of stiffness to the overall structure and the complete assembly should allow accurate one-setup machining.

I went through the same process for the chain side part and ended up with the following arrangement:

Here's the donor material that will become these parts:

I am pretty busy with work these days but hope to get to these before the castings get back to me.  For the ADV members in our viewing audience that work I need to get done is 2WD stuff!

Chris

Madame Tussaud's Motorcycle Parts

Parts Parts Parts!  I picked up the molds and wax patterns for the first 2 parts from my friend's place Metal Kinetics.  His guy did a great job on the molds and wax patterns.  They are nice big pink silicone molds that should be good for at least 100 parts.

The small 3rd piece for each mold is to make the cored out area inside the footpeg bracket area as shown in the image below:

The jagged edges look haphazard but do a very good job of keeping the mold parts aligned.  The wax patterns looked great with a nice smooth surface.  All the bondo and primer work I did was well worth the effort.

The whole shipment makes me feel like I'm making progress.

I sent 4 of each part out for to Harbor Castings for investment casting in 4130 steel.  They will also heat treat it to an "N" condition to remove internal stresses and match the tubing temper.  I am keeping 2 of each wax for display purposes and in case there are any quick modifications needed for a 2nd revision.  It is easy to modify the pattern using a soldering iron and wax to add or cut away pieces for design changes.


Now for something completely different here's one of the diamonds that Gui was making a ring for at his shop:

It was big and beautiful!  And could fund my motoring projects for a few years, at least!  Unfortunately he needed it back.


Hopefully the casting won't take too long and I'll make another post as soon as parts come back.



Chris

Boxes!!!!

Of parts!!!!!  Like Christmas in June.

More to come....