Backfiring KTM

[rf928]

I just bought a brand new KTM 350EXC-F (dual sport) and love it. I was riding along on the road when I discovered the bike became a lot louder. Look back and the spark arrestor is missing, so I back tracked and low and behold there it is in the gravel on a county road. Anyhow, I put it in my pocket and when I arrive back to the farm it is missing... again.

The thing backfires a LOT now, worse than what I figure is "normal.". I know these dual sports are programmed to be very lean, but this is really annoying how bad it sounds. Is it going to hurt anything? Its not super loud and crisp, but it is certainly noticeable. I can live with the noise after a while, but just was wondering if its going to hurt it bad? I plan on going to the dealer and picking up a new one, (spark arrestor, NOT bike :P ) but not sure if its worth it.

[DragonGunner]

I've read that KTM come lean brand new.....with the arrester off your getting more flow and running a little leaner. You can richen it up with the airscrew until you get the arrester back on, if not then you will need to go up on your main jet.

[deathman53]

that bike has fuel injection. Go to www.ktmtalk.com and find the thread on how to de-smog and re-program the computer to make it fun like it should. Yes, that bike and the 500exc is heavily corked to pass epa crap. Gearing is way tall for most people anyway, almost to the point of unusable.