i just bought an 05 sportsman 500H.O. its only -5 C outside and it fires right up with choke and idles good, but if i give it throttle it sputters and wants to die. if i get on it after 10min. of idling it sputters but once i get going and warm it up more its perfect. any ideas, what should i try?

 

If mine the first thing I'd do is drain the gas unless you know it fresh and go through the carb and install a new carb kit along with a new plug,oil and filter,air filter..... You can see what I'm getting at. Basically service this new "used" machine from front to back,replace any thing that's needed and then you'll know exactly what you have. Plus you might be able to catch some maintenance items before they become a major problem. Guess I was a tech too long.

 

ok, but do you think a carb kit is necessary? because when i drive it it goes like hell

 

It ain't supposed to sputter! You might try some Seafoam or something similar and see if it helps. If after awhile if it doesn't,then you probably need to pull the carb.

 

when i give it choke, i can rev it normal without sputtering, then when i turn it off it sputters again until i drive it abit

 

any idea what would cause this?

 

I always run some Isopropinal (gas line antifreeze) in the winter. My 02 500 HO does the same thing if I don't use it. People put it in their sleds so ATV"s are the same. When it's real cold out I have to run part choke while plowing snow. Once the fan comes on the first time, i push the chock all the way off. I use 1 bottle, the small ones, for 5 gallons of gas. I also changed to an NGK Iridium plug, which helped out to. It gets cold in Manitoba and if you still have last summers gas in the tank, it will draw some moisture.

 

it was only -5 C outside though do you think gasline antifreeze would make a difference

 

not going to hurt by trying it. I'd personally run a couple doses of seafoam through it. Every Polaris I've ever known is a cold blooded beast from the get go. You can tell that even my EFI wants to fall on it's face before it warms up a bit but the injection system keeps it in check. Nature of the beast IMO.

 

doesn't seafoam have a fuel de-icer in it already? i put the whole seafoam bottle in and theres no difference