2007 yz 450 valve spec question

4 replies to this topic
  • 88motoman88

Posted December 27, 2015 - 03:02 AM


My intakes were all .10mm and my exhaust were .20mm. The spec calls for .10 to .15 intake amd .20 to .25mm on exhaust. Do i want to ne in the middle of that range or am i good were they are. Do they get tighter typically as they wear? Seems like they would Idk which males me think to set them closer to the higher number. So leave em or shim now?

  • grayracer513

Posted December 27, 2015 - 07:20 AM


That's where the factory set them when the engine was built. They're is spec. Leave them. 

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  • 88motoman88

Posted December 27, 2015 - 08:36 AM


Ok what so the only other thing is the fuel screw setting amd worn slide? Seems like its getting narrowed down. Any other ideas thanksfor allthe help it can be a pain trying to isolatethe issuses

  • grayracer513

Posted December 27, 2015 - 10:49 PM


You only asked about valve clearance.  You have other problems? 

  • 88motoman88

Posted December 28, 2015 - 04:40 AM


Yes wont idle right. It hangs, the idle screw has an effect but it takes awhile to change. I checked for exhaust leaks, i had alot of popping i turned the fuel screw out and it stopped popping but was very hard to start and i smelt gas real bad. After push starting it it did start ny kicking after. The fuel screw wasnt out enough i think. It syarted yesterday in the garage around 4 kicks. Maybe its good now but i havent changed anything

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