YZ426 wont start

3 replies to this topic
  • spiritaces

Posted August 08, 2012 - 10:11 PM


I got an 02 yz426 the other for an amazing deal, $100. I brought it home and tried to start it. It took quite a few kicks to get it started. When it fired I had to give it gas to keep it running. I decided to clean carb and air filter. I also changed the gas and plug. I tried again to fire her and like before it took quite a few kicks to get her started. I had the bike choked and took her for a run. It ran rough and when I took the choke off it died immediately. Also after only one minute or less of ride time the pipe was glowing hot. The radiator fluid is full btw. Also at this point I noticed that I can kick the bike over without the decompression lever. I decided to take the valve cover off to see if the valve train was okay. When I kick it over and watch the valves they all seem to be working and moving up and down fine. What at this point could a possible problem be? Any help would be appreciated. Thanks

  • etuke

Posted August 09, 2012 - 02:43 AM


off timing maybe?or valves need adjustment.

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  • Slow and Jerky

Posted August 09, 2012 - 05:01 PM


The glowing pipe is normal. But I would do a compression test (if you have a manual compression release). Tight valves/low compression could definitively be an issue. The jets in the carb have to really cleaned well, if it is something that has been sitting for any period of time I would soak the jets over night and put lots of air through them.

  • spiritaces

Posted August 11, 2012 - 01:27 PM


I'm going to try and check the valves today and then I will let you know about that

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