Belt Hitting the Clutch Cover

When the belt is rubbing the cover it depends on where the hitting occurs and the cause is one of several things, bad clutching meaning a bad clutch kit or one set up wrong, bad clutching from the factory and good example is the 1000S RZR hits the cover about 7 oclock postion on secondary, your secondary has square pucks, they have worn it and are slowing the close of the secondary, our round rollers fix that or a shaft spacing issue where the two shafts are too close together and our alignment tool fixes that or simply worn out clutches.

Any of these do not allow the clutches to open and close together and leave the belt "loose" to hit the cover.  

First step is simply see what you see, if you are going to make some kind of purchase then the HW Alignment tool would be my first purchase to check shaft spacing.

While purchasing that, if you have a secondary that has square pucks and they have not worn your secondary out then get our secondary rollers to install while using the alignment tool

Even if neither are your issue then neither are a waste.