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Compression release interfearing with valve adjustment xr400

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I'm adjusting the valves on my xr400. Having trouble with right side exhaust valve. The one the compression release operates. I adjust it once, bike wont start. I check it again, it's way too tight. Readjust, bike will start but, noisy on top. Check it again, rocker is sloppy loose. Just adjusted it again and been rolling it over and checking it. once it has the right gap, the next, sloppy loose. and I am making sure I'm up on compression stroke every time, bringing it o TDC just after intake valves close. I think it's got something to do with the decompression mechanism on the cam. the cam I took out (because of wear) had this removed. the cam I put in, still has it. I don't remember having this problem with the old cam. Have any of you experienced this? Any input will be greatly appreciated. Thanks.

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You have to be careful to not rotate the engine clockwise if you pass TDC, that will engage the auto decompressor. Also make sure the manual decompression cable has enough slack.

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Kick the engine through slowly several times until you hear a click from the top end this is the autodecomp releasing. Then, rotate the crank until the T mark lines up and you are ready to adjust the RH exhaust.

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the cam I took out (because of wear) had this removed. the cam I put in, still has it. I don't remember having this problem with the old cam. Have any of you experienced this? Any input will be greatly appreciated. Thanks.

With your current cam that still has the decompresser on it, did you also install the spring and plunger needed for it to interact with?

Edited by Trailryder42

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