My 2006 Arctic cat 650 v2 every now and then while I am riding it, when I am going slow, and I accelerate it backfires. Not a big loud backfire, but a small but noticeable one. I am not sure what to do. I have been running sea foam in the gas for the last 2 tanks, because when I bought it it had been sitting a while. It has seafoam in this tank currently.

 

my 700 did that today and a couple times before. when i bought the bike the dealer said to run carb/fuel injector cleaner in the tank and i shouldnt have that problem. IMO it shouldnt do it at all but it did work , i never heard it backfire but now im running seafoam and it does it.

 

It has been my experience that backfiring as you describe it is associated with a dirty carb. Dumping too much fuel into the cylinder and it cannot burn it all so it goes out the exhaust and burns causing the pop. I usually first notice it if I am running at full or near full throttle and suddenly release the throttle. I can get a rumble, rumble....POW! and the engine sometimes dies at this time.

It restarts easily and I take it as a sign to clean the carb and air filter and adjust the sir/fuel mixture screw if needed. Usually cleaning the carb and air filter is all it takes.

Mudslinginfool is you 700 an EFI? If so my guess is it is computer or injector related. Maybe air filter.

Plus, I always use seafoam my ATV just runs better with it. I can not explain why. But, since it works I am sticking with it.

SJ

 

yes it is a efi swampyjr. im thinking of going to a copperhead or dynatech cdi for an upgrade. Perhaps that will help. I thought it was kinda funnny ,the day i bought it and i havent even started it yet and the dealer tells me that. I should just tell them to find out why and fix it since they knew it would before i even started it.

 

I find it very wierd that they "knew" it would backfire before you started it? That sounds like a computer or CDI issue that they need to fix. I had a friend who had (I stress HAD) and EFI polaris. He had it in the shop after every ride to have the computer tweaked so it would run smoothly. At After about the 5th or 6th trip the mechanic let it slip that they had a problem with that particular machine before it was sold to him! So he had a little talk with the dealer owner and worked out a trade. He went back to a carborated machine and does not regret it.

A new CDI (or actually a ECU in the case of an EFI machine) may or may not change things for you. I would say touse that warranty NOW while you can.

SJ

 

yeah, i think i might just go to a different dealer(one ive delt with before as well as my dad) and see if he might know whats going on with it.

 

I have a 2007 AC 700 EFI, and the last few time I've road it, it runs for an hour or so and then it starts to backfire. But no only does it backfire it bogs out like it is choking itself out. I can not for the life of me figure out why. I have cleaned the air filter, I have pulled the fuel pump from the tank and checked the sock, and I am using lucas injector cleaner just as a try. Does anyone have any suggestions.