I purchased a 90 sportsman for my son for x-mas and it is getting hard to start.I have had it back to my dealer twice and it is still the same.I found out if you stand it up on its back wheeles for about 10 seconds it will start.Before I take it back to those jack asses I wanted to know if anybody might know what is wrong with it. They took out the pilot jet and cleaned it but that didnt help and also when you ride it fast and slow down and give it gas again it just bogs down. Please Help![img]i/expressions/face-icon-small-sad.gif[/img]

 

that sounds like a maladjusted carb.
but could be wearing in the carb that's causing it to flood.

first, prop up the rear end like it's going downhill and see if there's a change.
if it seems to dog, you most likely have a leak through the jet into the head.

try adjusting the float so the bowl ain't quite so full.