Well today on the traisl the 600 backfired about 15 times but it was only after I was going at high speeds and peirod of time. about 60-70 klh. Any thoughts?

And I also notcied I had a fair bit of dirt in my air intake box, should I grease up the seal?

 

I had the same thing happen with my '01 last hunting season. Somehow mine just went away but I was given a few suggetions that it may be a pinched breather hose or just some junk in the Carb. It was really weird with mine just all of a sudden running full steam and BANG and then a large loss of power. It was hard to start etc. but then the next day it was fine and that was last year.....

 

Sounds like it could be a main jet issue, make sure it is clean and the correct size. remove the 4 bolts on the bottom of the carb to gain access.. Also make sure your air filter is clean, blow it out from the inside of the filter out. and wash the pre-filter.

 

I checked the filter and I had a Sh** load of sand and mud in there... the lid seemed to be sealed tight, should I use some marine grease on the gasket to make sure its nice and tight? the pre filter was dirty but the k&n didnt seem to bad. It was the first time I didnt check it b4 a ride. One more thing b4 I left the rpms were low so I adjusted the carb with the screw and I noticed at one point when I was at idle it was up about 1400 rpm's just sitting there....could that be part of my issue??

Thanks guys

 

check your exhaust gasket 'donut' at the Y pipe manifold, they wear to nothing and then you have a leak causing backfire and lean condition.

 

The front exhaust donut (NAPA part # 31360) at the Y-pipe exhaust manifold auto replacement.

Also check the carb adaptor. I have replaced the carb boot/adaptor (p/n 1253415), the rubber gets weathered/dry rotted bad on some and may crack through.

 

Just had a 2004 Sportsman 600 in the shop..Owner stated in would only run with choke partly pulled.Checked airbox and it was very dirty.Pulled carb and cleaned main-jet..Still after re-assembly same problem..Checked boot (connects carb to head) and it was ripped really bad..Replaced it and now the atv runs fine.I now check all twins when they come in for service for same problem and most of the older ones are starting to crack on the end that connects to carb.I suspect since the carb has a bracket mounted to the frame and the motor torques when under load this movement after time destroys the boot.(carb mounted soild and motor rocks)

 

I think i replaced mine in 2003! (2 yrs old).
Have replaced the Hall sensor 3 times also...

 

Hey Jimmypsp700, Is it common for the boot that connects from the carb to the head to crack? I did a quick visual on my '05 SP500, which is having a backfire issue also, and it seems to be OK. Was the crack you speak of obvious or did you need to pull the plastic and tank off to get a better visual?? I don't see any leaks in my intake or exhaust. Thanks!!!!

 

Ok Im getting that o-ring today for the y-pipe, do those springs come off pretty easy or what? Any good tips to take those off with out losing skin off the knuckles?