Drag on transmission mainshaft excessive?

chaztuna said:

Has anyone replaced that bush with a needle bearing? Is such a mode even possible? You would probably need to turn down the right side of the lay shaft to get a needle bearing to fit.

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chaztuna said:

Has anyone replaced that bush with a needle bearing? Is such a mode even possible? You would probably need to turn down the right side of the lay shaft to get a needle bearing to fit.
These issues suggest that investing in a premium synthetic gear oil would be a no brainer.

Charlie K

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Just read the thread tha LAB pointed out, so it has been done But I am not convinced it would help that much anyway!

You need to grind the hardened layshaft to reduce the diameter at the end and provide a sideways location when fitting the ball race, that is part of what you are doing!

A needle roller might not achieve the sideways location?

Part of the layshaft issue is that the kickstart shaft has an internal bush for the layshaft, and is bushed into the inner cover! Two potential sources of excess clearance! A needle roller might fix one!

Don't forget that part of a racer's motivation is to throw that big lump of metal away!

Did a 200 mile ride yesterday. All went well. Neutral is now easy to find and it shifts smoothly. To recap: Replaced the clutch hub/bearing, primary chain, Barnett clutch, layshaft bearing (roller), final drive and mainshaft bearing, 2nd and 4th gear sets and all gearbox bushings. Set layshaft end play to .020. Thanks to all for the guidance!