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Shimmy

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Jan 3, 2007
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#2
oldrnyzr, Now i am no pro with 4 strokes but i would think that the honda shim would be different from a Yamaha because the honda is a unicam while the Yamaha is a DOHC engine. So, it might but you should just wait and get the proper one. Now if i am wrong be glad to correct me.
 
Joined
Jan 27, 2000
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#3
oldrnyzr said:
Will a valve shim for a CRF fit a YZF....???
Yes.

The 250's use a smaller shim than the 450's but both brands use the same shim.
 
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Nov 15, 2006
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#9
2 strokes for life said:
sixds, it ushally stands for Dual Over Head Cams.
You are the winner sir. The unicam sounds like a fancy name for SOHC or single overhead cam, although some hondas might be OHV (Overhead valve) with the cam lower in the block which uses pushrods to open and close the valves.
 
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#10
02yz426f said:
You are the winner sir. The unicam sounds like a fancy name for SOHC or single overhead cam, although some hondas might be OHV (Overhead valve) with the cam lower in the block which uses pushrods to open and close the valves.
The unicam uses one cam in a cassette type of holder. The single cam rides over the intake valves and uses a shim and bucket design to open and close the intake valves. From the single cam there is a rocker arm that opens and closes the exhaust valves. Pretty trick set-up and makes it very easy to check and adjust the valves.

DOHC. Double Over Head Cam. Uses two cams. One cam for the intake valves and one for the exhaust valves. Modern thumpers use the shim and bucket design and older bikes like the XR line, use adjustable rocker arms.

To my knowledge, Honda has never made an over head valve engine using pushrods. This is a design used by older British and American made engines. Honda had the overhead cam design way back in the 60's and possibly before.

Just my $ .02