Author Topic: M21 kickstart ratchet pinion gear/bush  (Read 560 times)

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M21 kickstart ratchet pinion gear/bush
« on: 09 June, 2017, 10:27:39 »
I am rebuilding a gearbox for a BSA M21, and need to replace the k/start ratchet pinion gear, I have two old gears and bushes and both are quite a loose fit, I have a new gear and the ID is the same as the old ones, are the bushes prone to wear? it just seems odd that the old and new gears have the same amount of play on both bushes, all opinions appreciated. cheers, Ralph. 


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Re: M21 kickstart ratchet pinion gear/bush
« Reply #1 on: 10 June, 2017, 09:33:06 »
No direct M21 experience, but with similar setup on A10, Kickstart pinion rotating on a bush on mainshaft, my observations based on looking in many boxes, is that the teeth on the pinion wear and the bushes wear. Not noticed any significant wear on the inside diameter of the pinion.