Another backfire, popping question

2 replies to this topic
  • silveradoss

Posted July 11, 2004 - 04:29 PM


Halfway through a ride last week my bike would backfire, and pop on deceleration. It is weird because it ran fine the first half of the day. I am thinking it is the fmf factory 4 silencer ( air might be leaking where the midpipe meets the header)but I have had the silencer on for about 3 months now and I think the sealant( silicone )might have burnt off where the pipe meets the silencer. I just cleaned the carb, adjusted the air screw and tightened the air boot where it meets the carb, other than that I dont know what else to look for. Could the valves need adjusted? :thumbsup: I forgot to mention it was about 85 degrees and humid so I dont know how it would have gotten lean??

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  • racerxj17

Posted July 11, 2004 - 04:49 PM


check and make sure that all your exhaust connections are air tight, generally you are right; back firing on decelleration is caused from leaky exhaust, dont be alarmed. :thumbsup:

  • Fastest1

Posted July 11, 2004 - 07:14 PM


Did you try adjusting the fuel screw during the day? Did it help or did it still pop?

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