need help shimming valves

measured my vavle clearances today inlet was.6mm and exhaust was .8mm anyone tell me what size shims i will need?

cheers

It depends on what size shim is fitted to the bike. You need to know that first, they can all be different. Once you know the shim size you can work out what size you need to bring the clearances back within range.

You need a smaller shims to open up the clearance. By adding smaller shims you are lowering the valve bucket (the shim sits underneath it) and increasing the size of the clearance between the bucket and the cam.

The standard range is

Exh 0.17mm to 0.22mm

Inlet 0.10mm to 0.15mm

working on the measurements you have then you will need a shim that is a least;

.4mm smaller than the one fitted for the exhaust.

.9mm smaller than the one that is fitted for the inlet.

I would open the clearances up to the middle/higher end of the range.

Clear as mud

Start going back through the posts and using the search function. There's heaps of info on these things. Also look at the post on the CRF250 and YZ250f sites. There are posts with pictures on the steps. The basics are the same.

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