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Need some valve advice (measurement)

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So I go to measure my intake valves... left one is spot on but the right one is very tight. The smallest feeler gauge I have won't even fit into there! How do I measure the valve clearance to determine the correct shim size?

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A=(B-C)+D

A= The shim that we are trying to get

B=Current Valve clearance

C=Valve clearance u are aiming for...

D=present shim thickness....

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Did the bike still start with the right that tight?if you couldn't get the smallest gage in there it sounds like it is at zero.at this point it is trial and error untill you can get a gage in there to have something to start with to use the formula.I would put in the next two sizes smaller and you might get lucky the first time

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pull the shim out and put in one that is .005 smaller than the one that you have in there. It should be close.

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they consider that side the hot side of the 2 valves.you dont have to buy a shim you can sand it down on a flat surface and measure with calipers or mices as you go,If your doing this alot ,like every other ride this means the seat is getting moosed.eventually It will need a valve cut and go with aftermarket,kibbliewhite or ferrea stainless valves.z force racing on ebay did a great job for me.

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Your valve is worn out it should be replaced. If you shim it it will not stay in spec.

Crf431 you cant sand down a shim!

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post op report:

Well I pulled the shim out.. It was a 1.60. Got a good friend of mine to hook me up with a 1.475. After replacing it and checked clearance again... voila! Spot on! He also gave me a 1.45 as well just in case. Now she runs like a top and starts first-kick! :applause:

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kyleo,you most certainly can sand down a shim,ive done it many times,and Im not the only person to do so.

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