Dr. Evil Transmission expert comes to visit!

Dr. Evil at work!Gear Cluster BEFORE the conversion!
Gear cluster AFTER that conversion! View of 1938 Harley foot clutch



on Saturday 2-13-2010 the infamous Dr. Evil drove from his abode in Hershey, PA to my shop in Sterling, VA to help me customize the Porsche 901 transmission for the X-bike. Dr. Evil recommended I go with a 3 speed gearing. I argued with him for awhile but he finally won out by convincing me that with the foot clutch and jockey shift a 3 speed would minimize shifting time and really wasn't needed due to the already high torque to weight ratio that the bike would produce (able to overcome high gearing easily). Also, dropping enough gears would lower the tranny weight significantly and sure enough when we were finished at the end of the day 28 lbs. of gears, bearings, shift forks, and shift rods were dropped!

28lbs. dropped

Dr. Evil was calling the moves; swap 5th for 4th, get rid of Reverse, 1st, and 4th and I was cutting, turning, and tigging everything he needed to make the conversion. Now I'm working on locking the differential, cleaning everything, and replacing the main thrust bearings and a few others. Re-gasketing and then re-assembly. I'll probably be posting alot of the tranny work more as I go along the next few days.

Here's the conversion pattern comparison: