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.....??

Visit the ThumperTalk Store for the lowest prices on motorcycle / ATV parts and accessories - Guaranteed
  • 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:

Related Content


2016 YZ450 by CaptainKnobby

Dirt Bike   Dirt Bike Technical Forums   Suspension
  • Hot  59 replies


Dirt Bike   Make / Model Specific   Yamaha   YZ 400/426/450
  • Hot  30 replies

Megabomb Fitment by 288yz450

Dirt Bike   Make / Model Specific   Yamaha   YZ 400/426/450
  • 1 reply
WR Camshaft Swap Info - last post by jamesm113

WR Camshaft Swap Info

  • 0 replies

James Stewart back on a YZ450F by YamaLink

Dirt Bike   Special Interest Forums   Pro Racing
  • Hot  47 replies

Join Our Community!

Even if you don't want to post, registered members get access to tools that make finding & following the good stuff easier.

If you enjoyed reading about "" here in the ThumperTalk archive, you'll LOVE our community. Come join ThumperTalk today!

The views and opinions expressed on this page are strictly those of the author, and have not been reviewed or approved by ThumperTalk.