2001 WR426 timing. Help!

3 replies to this topic
  • cooptroop123

Posted February 29, 2016 - 07:57 PM


I recently bought a 2001 wr426 that isn't starting and I suspect the intake cam timing is a tooth off. a bit of a backstory, I've gone through the basic stuff like cleaning the carb, changing the spark plug and still no start. Feels like it has decent compression based on how hard it is to kick through TDC but I haven't measured it yet, will do it soon. So I've dove in a little deeper, checked valve clearances and they are okay, the exhaust valve clearance is at the low end of the spec in the manual but I don't think that would prevent starting.


Checked the timing next and it doesn't line up like the picture in the manual, can someone tell me from the pictures below if the timing is right or if it needs adjustment?








any help is appreciated, I'm losing patience and really want this thing running soon!



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  • nilknarf

Posted April 16, 2016 - 05:55 AM


If I recall correctly, the dots on my '01 intake cam line up with the top edge of the head, while my exhaust cam has been set to YZ timing: rotated one tooth clockwise from the dots being horizontal (and my WR seems to run pretty strong)- it almost looks like yours is set up the opposite way (intake cam rotated clockwise while the exhaust cam dots are level with the top of the head)... check out this post: http://www.thumperta...to-help-others/

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  • BigMac

Posted April 16, 2016 - 09:12 AM


I was just getting on the forum to post the exact same pictures. My cam timing marks look just like yours with the intake cam seemingly retarded one tooth with 14 links between mark (stock 13 links, YZ timing 12 links, according to WR FAQ). I just recently purchased my bike as well and don't know much about its history and was opening it up to check valve clearances (which are WAY too tight) when I noticed the timing marks. My bike starts and runs fine, in fact I just rode it to the convenience store yesterday. If anyone could shine some light on this I would much appreciate it also!

Sorry, not much help to you coop!

EDIT: after further reading and pondering I realize the 12/13 between the marks is counting the pins between the top (12 o'clock) timing marks on the cams, not links between the outside timing marks as I had assumed, sorry for the confusion! With that revelation I see that my cams are actually the factory 13 pins apart and when aligned properly it seems to me that the cams are timed properly in relation to one another but are both retarded one tooth at the crank gear (or the crank is advanced one tooth, however you want to look at it)

Edited by BigMac, April 16, 2016 - 10:06 AM.

  • BigMac

Posted April 16, 2016 - 09:16 AM


What mine looks like:
ImageUploadedByThumper Talk1460826912.571689.jpg ImageUploadedByThumper Talk1460826924.427115.jpg ImageUploadedByThumper Talk1460826942.285472.jpg ImageUploadedByThumper Talk1460826954.658312.jpg


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