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Are the stock shim sizes from the factory the same?


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Bought my bike from a dealer. No idea how many owners it has had, much less if it's been shimmed or how many times. Trying to figure out if my bike has ever been shimmed before.

I'm wondering, did the '05 250X all come with the same size shims or do variations in valves/heads result in Honda using different shim sizes to get to the correct clearance spec on a bike-by-bike basis?

If the stock shims are all the same from Honda, what are the stock intake and exhaust sizes?

Thanks!

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There all different.

You will know if they have been shimmed before buy just riding it hard for a day and recheck them. They move fast after the first shimming.

From the factory they are all different, Hell left and right sides will probably be different.

That being said valves do not move fast after shimming Its all how you treat your bike... If your constantly bouncing off the rev limiter and dont watch and change your oil often ya valves will wear and stretch much quicker. I have my 04 250x on its 10th rear tire, never needed to rebuild the top end. I shimmed the exhaust valves about 2 years in as they were just slightly loose (only had to go up 2 sizes in thickness), intakes were spot on. a year after that i popped in a 06 CRF250R cam and did the pink wire mod and im still spot on with the factory shims on the intakes, and the now 4 yr old shims on the exhausts.

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From the factory they are all different, Hell left and right sides will probably be different.

+1

That being said valves do not move fast after shimming Its all how you treat your bike... If your constantly bouncing off the rev limiter and dont watch and change your oil often ya valves will wear and stretch much quicker. I have my 04 250x on its 10th rear tire, never needed to rebuild the top end. I shimmed the exhaust valves about 2 years in as they were just slightly loose (only had to go up 2 sizes in thickness), intakes were spot on. a year after that i popped in a 06 CRF250R cam and did the pink wire mod and im still spot on with the factory shims on the intakes, and the now 4 yr old shims on the exhausts.

Not 100% factual. Usually new valves will seat them selves and require 1 shimming from the factory or new rebuild. Then they are good to go until you start loosing clearance from the seats and faces of the valves breaking down. What shovle65 was trying to say is that if the bike was loosing clearance due to valve seat or faces are damaged they you will loose clearance right away typically.

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