on my 700 efi whenever i let off the throttle it backfires. It only does it when warms up. I'm not sure what it is, spark plug or what. Its already got 3000 miles on it. If anybodys got an idea please let me know.

 

my guess would be spark plug, air filter or fuel. what octane do you run? By the way welcome to the forums!

 

Thats what i was thinkin, but some people say somthing about the throtle cable. O, ya i run regular 87

 

my 400 used to backfire but now i run sunoco 94 octane and now it doesnt backfire

 

the octane level shouldnt make it back fire. maybe the spark plug gap is too far making it run hotter. hard to to tell w/ the efi.

 

thanks i never thought about gapping it, it was runnin a little hot, do u know how far too gap them, maybe i should just get new ones they do have 3k miles on them

 

well i would w/ that many miles. the book says rc7ys for the plug gapped at .035".