06 450 Small Back Fire While Kicking Over

7 replies to this topic
  • Troutman

Posted June 06, 2007 - 11:15 AM


Lately when I go to start the bike, (for the first time in the day), I am getting a backfire after those few initial kicks. After my second or third kick it will start an run great, like a raped ape. After it is hot it always starts on the first kick with no back fire. I am running at about 5500ft with the 48 pilot and 62main combo, the bike is perfect otherwise and has about 60hrs on it. Any thoughts?

  • grayracer513

Posted June 06, 2007 - 11:44 AM


They seem to like to do that. My '06 does it sometimes, and in fact, every now and then, it will pop once just as the engine stops. It's fuel that went through the engine to the exhaust without igniting being set off by a flame from the exhaust port. Exciting, but harmless.

  • berudd

Posted June 06, 2007 - 12:27 PM


check the valves

  • 2wheels-drz

Posted June 06, 2007 - 01:58 PM


mines does it too.. always in the first kick, then starts second(when cold), and likes to throw some fire out the back on decel....its normal

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  • Troutman

Posted June 07, 2007 - 07:42 AM


It did not seem harmful and it's reassuring to know that it happens to other people. I will not worry about it anymore. Thanks for the responses.

  • justgotmine

Posted June 13, 2007 - 07:51 PM


i love my bike ..... it breaths fire too!

  • Ga426owner

Posted June 14, 2007 - 06:12 AM


differing humidity levels affect this......adj fuel screw....after it is warmed up.

  • walton_404

Posted June 19, 2007 - 09:21 PM


I have the same problem, and when I rev I get a back fire and flame, every time! Now I seem to have loss of power out of the corners, like I'm in a higher gear then I should be but I'm not! It's not clean power at all! Have not changed the jetting yet, it is from factory but always seem to run fine. Any suggestions? Also appears to be using oil, I may have 65 to 75 hours on it. Piston and rings??? Already? Who knows, any suggestions? I'm no pro so I don't think I abuse the crap out of it and I drop the oil every four to six hours. I heard the clutches are weak in them due to lack of oil, could this be the issue as well?

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