My 650 started backfiring

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Apr 4, 2002 | 06:54 PM

bigred650

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Weekend Warrior

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After i installed a twin air filter and took off the inspection cover it backfires when you let off the gas. Any ideas, does that mean it running lean?

Apr 4, 2002 | 07:52 PM

stebob

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You may need to turn your air mixture screw out a turn or 2. I recommend going in 1/2 turn increments however.

Apr 5, 2002 | 02:12 PM

trx450

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Backfires: too lean----out carb(s)/ too rich----out exhaust

Apr 5, 2002 | 02:46 PM

STAKK

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The stock air screw's are 2,1/4 turns out I have mine out 3 turns, thats what the dynojet kit recommends.

Apr 5, 2002 | 06:17 PM

Area51

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Did you just install the Twin Air filter, and then the problem started with no other changes, or did you re-jet also?

Apr 5, 2002 | 06:19 PM

Area51

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What inspection cover did you remove?

Apr 6, 2002 | 06:25 PM

bigred650

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I just installed the twin air filter my jet kit has no come in yet. The inspection cover is right below the handle bars were your pour the antifreeze in. It pulls in alot more air without it.