I recently bought a Jetkit and i have a bad backfire in high and low rpm...
i know that backfires is ok in high rpm's
but it also backfires when its running on low rpm's

any chance i insatlled the kit wrong? it's very ez so i dont think so

can u give me all the reasons why it backfire in low rpms?

10x alot!!!

 

Backfiring is NEVER ok at any RPM's. Your most likly running lean on the bottom and top end. First of all, jet kits aren't as easy as they make them sound. I found it much easier and cheaper to go buy jets and the NCVQ needle from Yamaha. I would suggest turning out the fuel screw another quarter to a half turn and putting a larger main jet in. Did the kit supply a larger pilot jet? Also, is this for your DS or another quad?

 

This problem appears on 2005 std. predator...
anyway, the pred is not mine, its a friend's quad...
Any idea what can cause the backfire problem?

maybe it becuz of rich fuel flow ??? he got a fuel and air needle if i understood what he said...

10x

 

I just told you...it's because he's got it jetted to lean. Are you sure it's backfiring and not babbling at you? The difference being backfires are a loud crack while babbling is a softer low pitch noise.

If you can't fix the problem I say ditch the jet kit and get jets from Polaris. Post on the Polaris forum to get recommendations on the proper jets to buy.