450FX, when to check valves

4 replies to this topic
  • cowboyona426

Posted August 29, 2016 - 07:45 PM


Bike has 11 hours on it now, prepping it for labor day weekend dirt shredding.  Should I be checking the valves yet?  I seem to remember 20 hours being the starting point on my 06.  Yes I've read the manual and know what it says, FYI.

  • RMK800

Posted August 29, 2016 - 09:35 PM


I have 45 hours on my FX, starts so easy still. I'm waiting for winter to check. I personally wouldn't worry about with those low of hours. I should have took a reading when I first got the bike,o'well.

Edited by RMK800, August 29, 2016 - 09:47 PM.

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  • Super_Davee

Posted August 30, 2016 - 09:19 AM


I have about 1,500 street miles on my 16 WR450, and they were all in spec. The right intake valve was at .14 (.13 is spec) left intake was at .152, exhaust valves both dead in the middle. 

  • grayracer513

Posted August 30, 2016 - 09:57 AM


Occasionally, a new valve and seat combo will experience some initial "settling".  Doesn't happen often, but it never hurts to check.  Bear in mind Yamaha has always tended to build to the minimum specified valve clearance.  Just because they are at or near minimum is no reason to disturb them.

  • NW_drZ

Posted August 30, 2016 - 10:41 AM


At 70 hours I had one intake valve slightly out of spec (tight). The rest were good and where actually at the high end of the spec threshold

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