7 replies to this topic
  • firemanmatt82

Posted December 19, 2009 - 05:44 PM


So I just got my 01 Yz426 all back together after a little freshen up and now I have a huge problem. The damn thing never had a problem starting and ran great. Now I have to kick it 20 times to get it started and it wont let me throttle up half way before it dies on me. I check everything I could think of that might cause me a problem, and have turned up nothing. Please Help

  • suttona

Posted December 19, 2009 - 09:28 PM


what did u freshen up ?

  • Valkrider15

Posted December 19, 2009 - 09:32 PM


Check, Double Check, Triple Check the valve timing. One tooth off will make it impossible to start - Proper timing will start it on one kick. Trust Me - I know!!


  • suttona

Posted December 19, 2009 - 10:11 PM


also make sure theres no 450 decompression exhaust cam installed or the timing has to to be set diff. does your bike have a decompresioin lever on the handlebars?

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  • Numba68

Posted December 19, 2009 - 11:46 PM


I'd check the cam timing

  • mxmaddman

Posted December 20, 2009 - 07:44 AM


timing. did it get new seats cut? If the timing is correct just do a leak down test. clean the carb while your at it.

  • firemanmatt82

Posted December 20, 2009 - 10:29 PM


what did u freshen up ?

I did a very deep clean on the bike. Replaced all my plastics, graphics, and working on picking out an exhaust for it. For a bike I bought for 1700, I didn't plan on spending five hundred right off the bat. But it looks great. Just runs like $hit as of right now.

  • matt4x4

Posted December 21, 2009 - 05:29 AM


CARB!!! - sounds like one of your jets is plugged.
Remove the carb, take it apart, clean it thoroughly using carb cleaner - this is typical if your bike sat for a while with no gas going through the carb.

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