Saturday, July 16, 2011

Back to our scheduled programming

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

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

Friday, July 15, 2011

And Back to the Mill

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