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!

Visit the ThumperTalk Store for the lowest prices on motorcycle / ATV parts and accessories - Guaranteed
  • 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)

Related Content


First Hare scramble tips by dhend8

Dirt Bike   General Dirt Bike Forums   General Dirt Bike Discussion
  • Hot  33 replies

Michigan Motocross Tires by 288yz450

Dirt Bike   Dirt Bike Regional Discussion   North
  • 1 reply

Need help by Goforaride

Dirt Bike   Dirt Bike Technical Forums   Suspension
  • Hot  68 replies

100 hrs on 2014 yz450f, shim valves or replace them? by ttr230rider6

Dirt Bike   Make / Model Specific   Yamaha   YZ 400/426/450
  • Hot  79 replies

yz400f throttle bog by yz400fmaniac

Dirt Bike   Make / Model Specific   Yamaha   YZ 400/426/450
  • * * * * *
  • Hot  28 replies

Join Our Community!

Even if you don't want to post, registered members get access to tools that make finding & following the good stuff easier.

If you enjoyed reading about "" here in the ThumperTalk archive, you'll LOVE our community. Come join ThumperTalk today!

The views and opinions expressed on this page are strictly those of the author, and have not been reviewed or approved by ThumperTalk.