Back Fire

6 replies to this topic
  • paul69

Posted March 17, 2006 - 08:54 PM


Hello I have a WR426F and when i ride home from work sitting on 110 Ks for a bout 2 Ks i come off the throttle and sometimes it back fires any ideas??

  • Gerry B

Posted March 17, 2006 - 09:39 PM


turn your pilot screw out about a half turn.

  • paul69

Posted March 17, 2006 - 10:03 PM


The pilot screw is out about 1 1/4 turns (the one trough the float bowl) .
would the hot weather make it do yhis its around 38C.
does turning it out richen the mixture?

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  • flintlock28

Posted March 18, 2006 - 05:22 AM


SOME backfiring upon de-celeration is normal....if it back fires a lot upon de-celeration, than you are too lean.
Yes, turning the screw so that it comes out does make the bike richer, while turning it in leans it out. I highly recommend an aftermarket fuel screw like the Zip-Ty or an equivalent.

I like to adjust the fuel screw so that I get an occasional back-fire upon de-celeration; this is where it seems to run best.

  • paul69

Posted March 18, 2006 - 07:56 AM


Thanks for your help

  • BergArabia

Posted March 18, 2006 - 08:47 AM


Paul where are you in Oz? And what kind of sprocket setup and tires do you run for commuting on the WR?? Seems a different but somehow mildy appealing idea..

  • paul69

Posted March 21, 2006 - 10:50 PM


I live only 2km from work and its more or less out of my road a long straight then im at work. My bike still has the standard tyres and sprockets but i need a new rear tyre , im looking at a Metzeler ENDURO 3 SAHARA.
i live in WA oz

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