Help Valves

3 replies to this topic
  • DAVID146

Posted February 26, 2009 - 05:48 PM


I need to adjust my intake valves the middle is close to slam shut. The outside are at a .102 and have a 170 in them. The middle has a 155 to 160 in it. What should the two outsides be shimed to along with the middle?

I was thinking that the two outside need to be a 165 and the middle needs to be a 150 to 155 depending on the measurement of the shim.

one more thing can they each measure diffrent as lang as they are within range.

  • grayracer513

Posted February 26, 2009 - 05:53 PM


The head needs a valve job immediately. The only way that would not be true is if one has just been done. You can shim the center intake if you like, but it will need it again in 2-5 hours, and running the engine like that is risking dropping a valve.

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  • DAVID146

Posted February 26, 2009 - 06:05 PM


THANKS GRAY! I know it needs valves that's next weeks project. I was just trying to ride a few times Friday.

  • grayracer513

Posted February 26, 2009 - 09:12 PM


I really wouldn't risk doing so. I do know the feeling (been there with a YZ250F), but the results could be disastrous. By your description, the center valve may take a 145, and I don't know if you'd even be able to find one.

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