yz400f timing

7 replies to this topic
  • lover_boy111086

Posted November 19, 2007 - 08:23 AM


ok i havea 1999 yz400f sombody told me it had from the crank up 426 in it how would i go about finding this out cause i think i might have dropped a valve the other day it wont start and when it does it has no power and the exhaust is no wear near as loud thankx o ad i need to know how to re time it when i get read yo tear it down

  • jayh300

Posted November 19, 2007 - 08:36 AM


at the top of this forum in the common threads, there is an online manual, I would start there.
also does it still have a decomp lever ?

  • lover_boy111086

Posted November 19, 2007 - 08:40 AM


yea it still has all the decomp on it can you give me a link to the online manual thanks im new to this

  • jayh300

Posted November 19, 2007 - 08:51 AM


that will make it a little easier. a lot of those have been upgraded to the newer exhaust cams, either hot cams or the 450 cam. Mine has and it is a great improvement for them. the hot cams times like the regular cam, but the 450 cam is different.
Not sure how to tell the diff between the 400 and the 426 from the outside.
Pull the valve cover and timing plugs and see what you find......

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  • jayh300

Posted November 19, 2007 - 09:05 AM



  • jayh300

Posted November 19, 2007 - 09:07 AM



  • grayracer513

Posted November 19, 2007 - 09:34 AM


You may have a problem with the online manuals. The last few times I have tried the link to the YZ400 book on the Aussie site, the file has been corrupt.

There is not one listed on the Euro page, so the next best thing is the manual for the 2000 YZ426, which should be very similar in almost every respect as far as procedures. The valve clearance specs for the 2000 models are the same as for the 400, but other listed specs, obviously, will vary. Still, the procedures laid out are 99% identical.

  • lover_boy111086

Posted November 19, 2007 - 09:52 AM


thanks all of yaw for the help i appreiate it wish me luck im gonna go start on it

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