2008 yz450f wont start

5 replies to this topic
  • moorejm

Posted June 19, 2009 - 04:12 PM


Got back from the trac last weekend and sprayed off the bike and put it up. I had to go out of town for a week and couldnt get to it until today. I cleaned the air filter, put on a pro taper throttle tube and new grips :worthy: and then tried to crank up the bike so I could chage the oil out. It took alot of kicks to get it going but it cut off after a minute or so. :lol:

I finally got it cranked up again and took it up and down the street a couple of times and it was backfiring like crazy on deacceleration. When I slowed down to an idle it just cut off. Now i cant even it get started. I put a new spark plug in and the old one was a bit black and sooty. Any suggestions???

  • husqy360

Posted June 19, 2009 - 07:38 PM


dirty carb.

  • Mav_10

Posted June 19, 2009 - 08:25 PM


Too much oil in the air filter.

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  • grayracer513

Posted June 19, 2009 - 09:50 PM


That could be it, or since it sounds like you didn't give the oil 4~6 hours to dry, you may have sucked some into the carb air jets.

It could also be water in the carb.

  • moorejm

Posted June 20, 2009 - 05:20 AM


Thanks for the advice, im going to check my jets today and I will keep you updated:thumbsup:

  • moorejm

Posted June 22, 2009 - 03:08 PM


I drained the carb and gas tank, recleaned and oiled my air filter and the bike runs fine now. I dont know if i got water in the carb somehow or if I had too much oil on my filter. Thanks for the advice I appeciate it!

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