I bought a new SP 450 this summer and have about 40hrs on it now....great riding atv, good power, seems it's built very well....but i am having a problem with it randomly stalling out. It just sputters and dies like it is out of gas. Then I can restart it with a little choke and she goes fine. The lights don't dim or cut off so it must be a fuel/carb problem??? But it's like it's either loosing spark or fuel. I have had it in to the dealer and of course it doesn't do it for them and they say everything looks just fine. They replaced the spark plug and got me a new air filter but that didn't solve the problem. Seems to happen more when i have been riding it hard and have the throttle pegged for an extended period of time and early in the mornings, but it is random. Most of the time it starts fine and runs great. I know there is a throttle position sensor that keeps the throttle from being stuck open but the dealer said that was ok too. Anyone have any ideas? Clogged fuel filter, blocked fuel line, dirty carb? I wouldn't think any of these would be the culprit beacause it is a new machine? Please help!!! Thanks in advance!

 

Seems like i have seen this alot with sportsmans my cousins son has a 500 carbed same problem. Have you fixed it ?

 

Welcome to the forums!I would check those few things you mentioned.... fuel filter, fuel line, and carb. Even though you only have 40hrs on it, I would first check the carburetor. Tear it down to see if one of the jets is plugged(main and pilot jet). It may have dirt in the carb, as that may as well be the culprit. If this doesn't help check the fuel filter and line. I will check in on the Electronic Throttle Control (ETC) as there was someone on here that had the same problems as you and he had the ETC replaced and that solved the problem. I will check back later today. Good luck.

 

Check your fuel vent line. My wife's hawkeye did the same thing after loong stretches of high throttle use. The vent line was restricted (pinched). If it happens again loosen the gas cap and see it it happens again. I found the pinched vent line and no more problems.

 

if its still under warranty i wouldnt start tearing it apart, unless you dont plan on them finind out for the warr. would be voided. you can check the vent hoses pretty easy and at least emitnate that. if it stumbles pulll out the choke to see if it comes out of it then you'll know its fuel related. make sure the gas shut off is open all the way stupid i know but it could restrick gas flow as well. cheap money to replace fuel filter but unless you got some dirt out of a can i doubt its ther filter w/ only 40 hrs.

 

before you go crazy check this. remove your seat and inspect the end of the snorkel where it fits under the tank plastic. upon hard acceleration these are deflecting upwards and closing off against the plastic remove the snorkel and trim a little matrial off 3 sides that way it doesnt choke itself off. seen a couple do this before if thats your problem. any way it will eliminate that issue. if thats it lets us know.

 

Check the vent tube on top of the gas tank., It must be pinched.

 

Well I've had it in 3 times to the dealer and my problem is still not fixed. It stalled out 4 times this weekend while I was hunting(all within a matter of minutes then all was fine). Of course it runs fine when the dealer has it so they can't fix what they can't see. They checked all the fuel lines, vent lines, air box snorkel, ignition, carb and fuel filter so I'm at a loss what to do now. I don't want to get stranded miles back in the woods and have to walk out. What do you think my chances of Polaris buying back this atv and giving me a credit towards another? I would guess the dealer would take it as a trade but they probably wont give me what i'd want for it. I'd rather try and deal with someone higher up. I don't think it would be considered a lemon because the dealer can't even see what's wrong. Anyone ever done something like this before?

 

i would guess you dont have a prayer of them buying back for what you want for it. you can trade it in but will lose some im sure. we have 3-400 miles on ours w/ 0 problems.