Serious Valve help needed


7 replies to this topic
  • ThrakenH04

Posted November 02, 2004 - 02:58 AM

#1

I checked my valves last night and I got .008, .008; .004, .004, .004. I dont think these are the correct clearances, what do I do to get them to where they should be. also I dont think the lobes are in correct timing with the punch marks on the cam sprockets.

  • Matt03wr250f

Posted November 02, 2004 - 03:29 AM

#2

i was talking to the guy doing the headwork today and he dumbed it down for me and as far as i understood was that if the clearance on the intake valves is the same they should be ok and the same goes for the exhaust, something about them lining up properly

  • ThrakenH04

Posted November 02, 2004 - 03:47 AM

#3

But my manual says the intake should be .020-.025 and my ex should be .010-.015 so if they are alot lower then that, wouldn't it be a big problem to have? Considering that I loose HP and Torque plus reliability and top-end longitude. Anyone else who has an 05 want to tell me what they got for their first valve check clearances?

  • YZ250F_Rider

Posted November 02, 2004 - 04:06 AM

#4

the 020 is in mm's not inches. Use the tolerances in ( )'s.

0.0039" - 0.0059" intake.
0.0079" - 0.0098" exhaust.

both measurements are fine.

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  • ThrakenH04

Posted November 02, 2004 - 10:09 AM

#5

the 020 is in mm's not inches. Use the tolerances in ( )'s.

0.0039" - 0.0059" intake.
0.0079" - 0.0098" exhaust.

both measurements are fine.

So in other words.....im good???????? and if so, when do you think thou shall check thou's valves once more?(using old enlish for some reason)

  • grayracer513

Posted November 02, 2004 - 04:15 PM

#6

Your motorcycle is precisely in spec. at .20, .20, .10, .10, & .10. As pointed out, the manual specifies clearances in millimeters. To convert, multiply inches by 25.4, or divide millimeters by the same number. Each .05 mm is roughly .0025 inch, and each .01 mm is .00039. That's pretty small. Don't sweat the details too much.

Most feeler guages these days have the metric equivalent marked on them as well as the English size, but the metric won't be an even 2 place value.

Your bike will use a .006 and a .004 to check the intakes, and a .010 and .008 for the exhaust.

Of course, if you buy actual meteric feelers, it's that much simpler.

  • YZ250F_Rider

Posted November 03, 2004 - 10:31 AM

#7

just for reference.

the clearance will never get larger. So all you have to look for is the smaller feeler being able to fit in between the cam and the lifter bucket.

And yes, your valve measurments are fine. Now get out there and ride it. :cry:

  • ThrakenH04

Posted November 03, 2004 - 12:52 PM

#8

just for reference.

the clearance will never get larger. So all you have to look for is the smaller feeler being able to fit in between the cam and the lifter bucket.

And yes, your valve measurments are fine. Now get out there and ride it. :cry:

lol, ok great. Thanks for the help everyone, I can finally put my mind at rest and go to practice this sunday at the Seminole Tribe Motocross Track.





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