I have a 1991 Polaris Indy 650, Model # 0910758, serial # 1840650 Mfg Date #0061990. The guy I got the sled from had ideas of turning it into a drag sled and to me the clutch has never worked right. I believe the primary was switched at some point and is not the correct for the sled. I have tried the recommended belt and it as to much slack in it. The clutch engages at about 4500 rpm with Polaris Belt #3211042. Riding today in very light fluffy snow I had to be easy on the throttle in order to engage the belt, could not go from half throttle to wide open as engine rpm would get to 5,000 and stop increasing, about 20-30 mph on the speedo. In the picture for the Polaris part book I labeled the parts with what numbers I have on my clutch. Sliding sheeve 480 092889. Any help on identifying the clutch and any other suggestions are appreciated.
Riding this weekend the clutch did better at engaging every time when accelerating. The clutch does say Polaris on the side, I just don't believe it is for the 650. It also seems that a fuel supply issues has surfaced when trying to accelerate after a wide open throttle run when letting off for the corner the rpm drops as expected but when trying to accelerate from the 4000 to 5000 rpm range the engine rpm won't climb and then the engine dies. The spark was checked and it was all good that's why I think it is the furl pump or fuel pickup as this doesn't happen when the tank is very close to full.
The clutch itself looks real and genuine to the sled, But its hard to tell. All indy primarys are interchangeable. What matters is the weights and spring set up you are running. Check buttons on the spider. Also see how much play you have side to side with the weights. Mine let go this weekend with the same symptoms. My weights had no bushings left.
All Polaris clutches used on Indys are not interchangable. Some of the clutches on the twins look identical at first glance but use a different offset. Use of the wrong clutch can wipe out the PTO side crankshaft seal. To be safe, a good rule is any clutch used on a Fuji triple will work on the other Fuji triples.
I agree with all the rest that Aritcat Teen said. It's very possible a good cleaning will bring back your performance. When cleaning, look for the stuff he suggests; worn bushings in the weights, worn main bushing, worn spider. To fix the weights is easy, the other issues will require purchase of specialty tools to disassemble the clutch and a bit of work.
2007 Dragon RMK 700 155", 2008 RMK 600 155", 95 Prowler 550 2-up, Really OLD AC Cheetah