can you guys tell me whats goin on?

5 replies to this topic
  • thumper4life

Posted December 08, 2001 - 06:10 AM


alright, last night it was probably 44 degrees outside, and the track i went to was basically a barn and it was about 58-66 degrees inside. i didnt have a bike, i took my friends bike. its a 2000 yz426. we put a c7 plug in it the night before. so anyways we get to the track i go in for my practice session. it stalls while im going through these very steep whoops, basically doubles. then it stalls after i ride over a table top and enter a 180 degree corner, then i get it started and then after i jump another table top and land on the table top, ride down, enter the corner, it stalls. it did it for a few more laps then after it did it the last time, i got off turned the fuel off and just walked it back to the pits. sometimes when it was running and id let off the gas, itd backfire or pop. can you tell me what needs to be done? any other info needed ill supply. thanx in advance

  • thumpy

Posted December 08, 2001 - 07:10 AM


Sounds like a lean condition to me. Did you monkey with jetting? If so, it may have been a loose nut behind the bars :)

  • thumper4life

Posted December 08, 2001 - 07:17 AM


well, its gotta powerbomb header and an e series silencer with no disks and he went up 5 on the main i believe from stock

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  • thumpy

Posted December 08, 2001 - 09:56 AM


Hmmmmmmm, it sure sounds like a fuel problem but I had a CDI unit take a crap on me once. It gave similar symptoms to what you're experiencing. Where the leads come out of the CDI box, you can wiggle them while the bike is running and if there's a problem the motor will cut out. If that checks out I'd start looking at the float.

  • Bill

Posted December 08, 2001 - 12:53 PM


It has an E-Series with NO discs?? Is he using the end cap or running it open??? If the pipe is capped and has no plates, it's going to be rich.

Why one (7) hotter on the plug?


  • thumper4life

Posted December 08, 2001 - 01:03 PM


well!!! he went to a 7 because he thought itd be better for the cold weather, he had a 9 in it because he fouled his 8 two weeks ago.
yes no discs, he has the eliptical end cap on it.

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