Need help 08 YZF 450

4 replies to this topic
  • mclean133

Posted April 10, 2011 - 04:49 PM


I have a 08 450 the bike seem's to be poping and backfireing when your are just off idle and when you get off the gas also i have played with the air screw it does not help what could it be.:cheers:

  • Family Man

Posted April 10, 2011 - 05:00 PM


How many turns out is your fuel screw?

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  • John#22

Posted April 10, 2011 - 05:01 PM


too lean on the bottom. it will get better when the temps go up. or you can richen up the slow speed circuit

  • mclean133

Posted April 10, 2011 - 06:26 PM


the fuel screw is 2 1/4 turns out and also the bike is all stock with about 10 hr on it.

  • dvn

Posted April 10, 2011 - 06:39 PM


If it sat all winter, your pilot jet is gummed up. Pull it and clean it or replace it.

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