then chanaces are it's not the carb, but most likely the secondary buttons are worn out and making it seem like its starting in high gear w/ no pulling power. imo

 

it does rev up in neutral, but i dont think it is reving as high as it should.
when i ride it, it doesnt cut out, it only goes about half of full speed. i hope this makes some kind of sense.

 

Secondary clutch button!!!!!!!!!!!!

 

yup. the buttons are the issue. that is exactlly what happens when the buttons in the secondary(big)clutch where out. there is 3 plastic pieces on which the helix in the transmission clutch(secondary) slide up and down on when the clutch twist to open. once they wear out they don't let the secondary open up correctly and drags causing this lag in power. id you take off the clutch and take it apart, you will see what were refering to. if you don't know how or think you can take it apart and reset it correctly, then you should take it to some one who can.

 

you could take a look and see if the valves need adjusted, while you're in there inspect the cam lobes, some of the older models have premature cam wear.

 

I am experiencing the same symptons with my Polaris '04 Sportsman 400. It started a couple of months age and has gotten worse. It will not idle unless it is up to operating temperature and has no power in high range. I checked the carb and jets only to find no obvious sediment or dirt. I installed new plug, fuel filter and no help. It runs fine in low range. BTW, I have been using this to plow lots of snow. It currently has 6800 plus miles on the engine and approx. 650 hours running time. Help! MTG

 

first of all, thanks to all that replied. cleaned the carb. made a huge difference in the rpms. the engine reved up much higher than before, so much so, it started to back fire thru the carb. after some advise, checked the cam. guess what. the exhaust lobe is worn almost round. guess i need some new parts.

 

yes, mine will but will not rev up in gear