Motorcycle Rider News Tech Tips

Want to get a similar effect of running with a six speed? Higher speed with reduced RPM's at a very affordable price? Why not change your transmission sprocket? The original has 32 teeth, and can be replaced with a 34 teeth sprocket from Belt Drive LTD. The change seems small but will produce a major difference. It is relatively inexpensive when compared to putting in a six speed.

Start by disconnecting the battery and then drain the fluid out of the outer primary case. Remove the outer primary cover, remove primary chain and clutch assembly, remove jack shaft. Go to the right side of the motorcycle and remove two starter bolts. Go back to the primary side and remove the jack shaft from the starter. Remove bolts from the inner primary, take off inner primary. Lift the bike off the ground and loosen the belt. Remove the two socket screws and lock plate to free the sprocket nut. Remove the left handed sprocket nut. It's easier if you use an impact wrench.

Remove sprocket. This is a good time to check the belt for any cracks or imperfections. To install do the process in reverse. Put the transmission sprocket together and then slip on to the main drive gear. Use red loctite on the threads of the nut. Apply clean engine oil on the face of the nut and the inside face of the sprocket tighten finger tight. Use the sprocket locking tool to keep the sprocket tight. Install pilot of main shaft locknut wrench on threaded end of the main shaft. Slide sleeve of locknut wrench over pilot and onto sprocket nut. Tighten sprocket nut to 60 ft-lbs. Maximum allowable tightening of sprocket nut is 45* of counterclockwise rotation after a torque of 60ft-lb. Do not loosen sprocket nut to align holes or nut will be under tightened. Insert two socket head screws through lock plate into sprocket holes. Tighten screws to 9 - 110 ft-lbs. After installing primary chain case assembly, adjust belt deflection.

Note:
It is good idea to replace all seals. The kit come with new nut, transmission seal, socket head screws and lock plate. The sprocket kit we used is from Belt Drives Ltd., and can be purchased at Twin Performance in Broomfield - 303-438-5700

Editors Note:
Ray Domenico, owner, of Twin Light Performance performed the service described in this article. I just hung out and took notes and pictures

Originally Printed in the January 2010 Issue