Jumped Timing?

1 reply to this topic
  • joehonee

Posted January 16, 2010 - 02:53 AM


While doing a tuneup on a recently purchased 01 YZ426 I checked the valve clearances and they were fine. When I moved onto the cam timing check however, I ran into a little problem. The intake cam was off 2 teeth and the exaust was off 1. I have corrected the problem but am trying to determine what caused it. Previous owner/mechanic error or is there an underlying issue with the engine. The tensionor operates well.

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  • grayracer513

Posted January 16, 2010 - 08:50 AM


WHen you did the re-timing, you should have checked the condition of the cam caps and saddles for evidence of the cams having seized, and also for signs of kinking, binding links in the cam chain. Otherwise, it's possible that the cam chain is simply too long, or that the sprocket on the crank axle is worn.

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