yz400f valves on 426\?

9 replies to this topic
  • kounkel321

Posted March 28, 2007 - 01:34 PM


anyone know if valves of yz400f will fit in yz426f? thanks

  • grayracer513

Posted March 28, 2007 - 02:34 PM


Why do you ask?

  • 642MX

Posted March 28, 2007 - 02:37 PM


I doubt it, they have different part numbers.

  • kounkel321

Posted March 28, 2007 - 04:43 PM


well im in need of some valves and i found a guy that has some spare ones off a yz400...just wondering i guess

  • grayracer513

Posted March 28, 2007 - 04:49 PM


Not sure, actually.

You can, however, use the OEM 2000 SS valves in place of the '01/'02 Ti valves. They're much cheaper. Be sure you use '00 springs with them, though.

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  • Birdy426

Posted March 28, 2007 - 08:51 PM


I'm not sure either, but I expect they will...I say that because the 01-02 Ti valves work in a 99 400 head just fine. I would expect all that stuff is 2-way interchangable if, as Gray said, you take the valve springs with 'em (and retainers and colletts)

  • TL426

Posted March 29, 2007 - 06:21 AM


Not sure, actually.

You can, however, use the OEM 2000 SS valves in place of the '01/'02 Ti valves. They're much cheaper. Be sure you use '00 springs with them, though.

arent the SS valves a pain compared to the ti? or is it the other way around?

  • grayracer513

Posted March 29, 2007 - 07:30 AM


Yamaha OEM valves of either kind are exceptionally durable. The main difference in the two as far as maintaining them goes is that the Ti valves are hard coated, and this coating is so tough that it is not uncommon to see 4 and 5 year old YZF's that have never needed a valve adjustment. The trouble is that like all Ti valves, the hard coating is quite thin, and the underlying titanium is not very hard, so once they show any significant wear, they rapidly wear from that point on, and need to be replaced.

Their stainless valves are also very tough, but the material is naturally hard through the face. They may wear slightly faster than the hard coated Ti valve, but the wear takes place at the same rate throughout the life of the valve, and the fact that you need to adjust them one day doesn't spell imminent doom. And as I already said, they're way cheaper.

  • bluebike1999

Posted December 17, 2008 - 07:05 PM


so, let me get this straight.
I know SS 99wr 400 valves do not fit 450's
but does a 99 / 00 stainless valve fit a 426?
yes you need to replace springs to suit the different weight, but the 400 stainless valve is the same dimensions exactly as a 426 Titanium valve? yes?

I'm sure Ive supplied SS valves for a 426, and even Ti valves for a 400 ( at customers insistance), but i just wanted to make sure that that was correct


  • grayracer513

Posted December 17, 2008 - 08:15 PM


The 2000 426 used SS valves that have a part number that is different from the '99 400. The '99 is 5BE-12111-00-00, 5BE-12112-00-00, and 5BE-12121-00-00, while the 426 calls for 5BE-12111-10-00, 5BE-12112-10-00, and 5BE-12121-10-00. This could indicate a minor revision, a vendor change, or something significant enough that it would cause the valve not to fit. I seem to remember that the PN's were the same at one time, though. The spring hardware is all the same.

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