Valve Questions

12 replies to this topic
  • kounkel321

Posted April 23, 2007 - 02:10 PM


I have a 2002 yz426 with 2 bent valves...i was just gonna get a different head, but ill prolly do the valves question is since the 02's have titanium valves should i put them back in it or get stainless steel valves..and if i do that, is it a must to replace the springs also? any help greatly appreciated!!

  • grayracer513

Posted April 23, 2007 - 02:39 PM


Using the '00 steel valves is a good low-cost alternative. But, yes, you have to use the matching springs, also from an '00. SS valves are nearly twice the weight of Ti.

  • crazyadam

Posted April 24, 2007 - 06:12 AM


Just make it eazy on yourself, and sent it to the good people at Mototech Performance! :applause: 888-942-MOTO in Glen, NH

They rebuilt my head for way less than new parts would have cost.
My head was Cooked, when I bought it, there was a valve dent almost .200" deep.
ended up with new valves, seats, springs, loaded, for less than a used head on e- bay.

I keep checking my valve clearance, but it has not changed in the 3 years since they rebuilt it! :excuseme:
good luck!

  • crazyadam

Posted April 24, 2007 - 06:18 AM



I guess maybe they did not charge enough?!?!?!

I can't seem to find them.

There are others out there, good luck finding the best choice.



  • kounkel321

Posted April 24, 2007 - 02:12 PM


i know one off a wr or yz400f fits right on, but some dude told me that one off a 03 yz450 fits right on that right?

  • kounkel321

Posted April 25, 2007 - 01:39 PM


cmon someone has to know.....??

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  • grayracer513

Posted April 25, 2007 - 02:12 PM


90% sure that the 450 head does not interchange.

  • MM73

Posted December 14, 2007 - 02:22 PM


Hello guys!
Is it possible to use SS valve from YZ 400 and 00"YZ426 to YZ 450,are they the same ?
...Sorry for my broken english ! :banghead:

  • grayracer513

Posted December 14, 2007 - 03:23 PM


Nope, they they won't fit.

  • MM73

Posted December 15, 2007 - 02:13 AM


Thanks !!!

  • MM73

Posted December 15, 2007 - 10:46 PM


Please,grayracer513 explain where be the difference ?

  • grayracer513

Posted December 16, 2007 - 09:40 AM


Please,grayracer513 explain where be the difference ?

The length of the stems and the size of the valve heads are different. The 450's have an entirely different head; the valve splay angle is different, and the head is 7mm shorter vertically.

  • MM73

Posted December 17, 2007 - 11:03 AM


Thanks really,grayracer513 :banghead:

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