98 yz400 valves

4 replies to this topic
  • bryan103

Posted February 08, 2006 - 09:19 AM


need to set valves but have no manuel,whats the seq. and clearence

  • YZ400FPower

Posted February 08, 2006 - 08:57 PM


um.ill check.pm me later ill have it ok!

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  • s3706

Posted February 09, 2006 - 08:21 AM



Where are you located in Texas, maybe I can help you with it. :thumbsup:

  • bryan103

Posted February 09, 2006 - 03:02 PM


in the waco area,i took it to the shop today, carb was all out of wack,running like crap

  • grayracer513

Posted February 09, 2006 - 04:12 PM


I believe the 400 is the same as the '00 426 (SS valves), which called for .10-.15mm at the intakes, and .25-.30mm at the exhausts. Try to double-check me on that.

The valves are to be checked at TDC of the compression stroke. If adjustment is required, carefully retorque the oiled cam cap bolts to 75 inch pounds (6.1 ft/lb) in 3 steps. (the manual will call for 86 in/lb, but that's too much, IMO)

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