HELP! 450f Burbling and popping

6 replies to this topic
  • moto17

Posted June 12, 2004 - 02:27 PM


I need help with a 03 450f that is burbling, coughing and popping at around the half throttle range. WHen you are riding it as soon as you start to cut back on the throttle she starts to sputter pop and cut out. It has a Pro Circuit header pipe and Ti 4 silencer, Main jet was a 165 tried a 172 that didnt help, it has a 42 pilot, the needle was in the stock clip postion tried one higher and then one lower. I checked the accelarator pump timing and it is good.
PLease help this getting to be vary annouying going up to doubles.

  • tzracer46

Posted June 12, 2004 - 03:09 PM


check your exhaust for a leak at the head

  • moto17

Posted June 12, 2004 - 03:19 PM


There is no exhaust leak at the head, all seems tight. Any other suggestions??

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  • ryno717

Posted June 12, 2004 - 03:26 PM


Try a new spark plug. My bike was doing the same thing and jetting changes didn't seem to help. When I put a new plug in and went back to my original jetting settings she ran like a champ. :thumbsup:

  • Gizabious

Posted June 12, 2004 - 04:23 PM


Try adjusting fuel screw (under carb), worked for me

  • moto17

Posted June 13, 2004 - 02:01 PM


Thanks i will try the plug.
The The pilot air screw i checked and it is at stock?

  • moto17

Posted June 17, 2004 - 06:41 PM


Just to let you guys know i got it running crisp again :thumbsup:
it was the throttle position sensor cannon plug. Cleaned it and resecured it, now its good

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