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Discussion Starter #1
Hi guys,
Does anyone know the sheave clearance specs (for belt tension) for the front clutch assy? Here's the details...
I’ve got a 96 sportsman 500 that was given to me (pretty beat up and way not running). After $1200 of drive train parts and carb parts it runs pretty good now… except when I first got it going a few months ago, I noticed I could hear the spinning front PVT drive clutch assy rubbing against the shroud a little bit. I messed with the mounting screws and brackets a little and it went away. I just got it back out to exercise it a little and after a pretty hard run through the woods the shroud is rubbing pretty hard again. It didn’t actually start until a while after I returned from the woods though… strange. Anyway, I pulled it apart and did the belt slack measurement and instead if 1 1/8 “ of slack I have about 3”. The belt is in good condition and meets all of the length and width specs. On the rear sheave assy (driven clutch) the belt rides clear at the top, level with the top of the sheaves. I assume this is normal.. At the front clutch (drive) the belt is laying directly on the shaft which I assume is ok for idle conditions. The sheaves assy, though, has just over 1/8” free play before they tighten against the belt edges. This doesn’t seem right to me. If that 1/8 extra extension of the outer sheave assy was not there then the shroud contact noise would also disappear.
I can see that the machine would probably run like that, just not as responsive or fast top end. Nothing mechanical seems to be worn or sloppy to the point causing this problem.

My question is: I don’t find in the service manual any spec for the sheave gap (front) other than the reference to the 1 1/8” belt slack requirement. It just says to add or remove spacer shims to correct the belt gap. In order to get the belt to that point I would have to not only close the sheave gap by the 1/8” slop, but also by quite a bit more to pull the belt up the sheath taper and actually remove a lot of real slack. That would take 1/4 “ of shims… don’t think so.

To my knowledge no one has ever had this assy apart to mess with the spacer shims. In fact I didn’t even see any shims on the shaft. (although I haven’t actually pulled the assy off the shaft yet. Don’t have a puller. Any workarounds for that puller tool ??) I can’t imagine what could have allowed this much lateral movement without pretty obvious indications. Does anyone out there know how much free movement (if any) there should be on the outer sheave engagement assy (front) and/or how far up the sheaves the belt should be sitting while not running? Do you actually have that 1 1/8” free slack in your belt?? Could my engine shaft actually be shifting? Any ideas or experience with this?

Thanks, sorry for my wordy explanation, but I’m a detail guy.

Also another question, my bike turns real hard and tends to pull to the side a bit while backing up and while being pushed forward. Is that somewhat normal for a beat up 96? Anything I should look at?

Thanks again.
John (JCM - Granger, IN… near South Bend)
 

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I don't know where you got that info , but your description of the clutch is right on the money. Are you sure that isn't a chain adjustment? I have a '96 300 and it's chain drive. As far as the noise, in the front of the clutch cover there's a tab on the frame behind the cover that gets bent every so often. Just bend it back to stop the noise. And yes they have a tendency to pull in reverse, plus they don't push for crap!!! Don't do anything to the clutch,it's right. Ant other problems give a yell.
 

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Discussion Starter #3
Thanks for the reply.
That's good to hear. I guess one of the logs I climbed over in the woods must have bent that mounting bracket. That rubbing noise was the original problem I had that caused me to pull the cover in the first place. I guess once I got the cover off I turned into a raving hypochondriac, although the belt tension spec was in the manual. I'll bump that bracket back and leave well enough alone. I'll stop calling my steering hard and instead start calling it good exercise. Kind of a paradigm shift for the head, huh...keep on trucking!
 

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on the older machines,coverwould warp from heat , they changed how they were made in 2001, if you can find a newer cover it will fix it, if your belt isnt centerred on the front clutch, add or remove shims from behind the rear one to get it centereed, front is called primary, rear is secondary or driven clutch, rear will come off without a puller, need a puller for front
 
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