i just bought this ATV a month ago from a polaris dealer. I told buddy before i picked it up to look over the machine and make sure its ready to go.. spark plug, filter, belt, oil change, brakes. When i picked up the atv he said everything checked out ok and its good to go. Trusting a dealer i never doubled checked.

I have only ridden it once for about 30 min since i got it. I decided to clean it yesterday and check a few things.. here is what i found. The oil has milky resido inside and its basically green/brown in colour, the paper air filter is dirty and also had a little milky oil resido inside the airbox, the spark plug was black, black, black, and the air vent hose off the oil tank has a hole just after the fitting and just before the pressure relief slit. ( i dont know if this causes any issues but i could never hear the gust of air when i tried to do the priming after the oil change.)
Anyways i did the oil change, changed the plug and put a K&N air filter in.
It still bogs a bit when i hammer the throttle from a dead stop, it just hesitates a bit. I decided to check the spark plug again and it seemed to be black again. Is this normal? Any help would be great.

 

They run better a little rich, the black plug I wouldnt worry about unless it has alot of buildup, I would worry about the milky oil, it may be getting antifreeze in the oil, could be a head gasket or the water pump, keep a close eye on this. As for the bog you might cure it with a good carb cleaning, let us know how things turn out.

 

In the next week or two i will be sending it to a dealer nearby to have them clean out the carb and put the dyno jet kit in. Once i get it back i will post the results. Does anyone know where the drain screw on the carb bowl is? I have the shop manual but i still can't seem to locate it. Even the idle screw i can't find. In the book it shows it on the side of the carb with a spring tension but i can't see this at all. Its probably staring me in the face.

 

look at he carb at the bottom of the bowl sticking out to your left side should be the screw to drain the bowl and there is a screw coming down with a lil handle that is your idle i thing that is how mine is but i have an old sportsman carb on my scrambler i will check my manuel if i get a chance but yea mine bogs at teh bottom from being to fat and the plug is black from teh same reason. i have the K&N air filter also. son't worry about the oild in the air intake. that is normal from hard riding the suction of the engine pulls it out the lined and will sometimes get on teh air filter and make it bog from restricting eth airflow and choking the engine. ive heard stuff on hear about the sportsmans having new oild that is green and the reely new stuff is almost clear so that is prob what you have so that is normal and it prob tursna a lil dark after it is run.