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Idler Gear Stuff


If you clearance is bigger than the amount of a standard thrust washer and can't get hold of thrust washers bigger than standard there are two things you can do.

1. Make sure your clutch housing is in good order (no dings or marks on it) you can make a thinner gasket to take up the play. You can get all sorts of different thickness gasket paper. Find one you think will do and with a bit of trial and error you should be-able to reduce the clearance down to within the limits of the free play (3-7 thou?)

2. My favorite way is to measure the clearance and work out the amount of clearance you need to get rid of. Then remove the housing and take it down to your friendly machine shop. Who will then machine the cover of the amount you need to remove. This also gives a really nice Finnish for your gasket to mate to swell!


Pre-A+ has thinner shafts of un-equal length. The longer shaft goes into the gearbox side.

A+ is the same length and the gear can be fitted either way.


You need to check the clearance before you mount the engine (if you're into that sort of thing ;-). Here's how:

Insert the idler gear with the thrust washers it came with into the gearbox. Bolt the end casing in place with the gasket. Tighten to the spec torque. Measure the idler gear float with a feeler gauge. It should be ~0.003". If it's more than that, and it always is, insert the appropriate OVERSIZE thrust washer. These are available from all reputable dealers. I forget what the oversizes are but they are stated in most parts manuals. Thanks to Johnny B I have a complete selection in stock for all my rebuild jobs :-)

BTW, don't try to shim the thrust with brass shims. Hardened steel is the proper material for the aplication. Brass will disintegrate from the load, leaving you with not only too much idler gear movement, but also debris in the gearbox.

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