Well tell me this, how does your slipper pad look after the 20 or so runs? Is it burnt? Also, has it become hard? If so, the slipper is way to tight, try tightening it all the way, and turning the nut about 1/4 - 1/2 out and see if your problem persists. See if it getting hot though.
Run a few minutes under high pressure loads, such as climbing and stuff. Touch the spur gear, see if it's hot. It will be warm, but if it burns you in the least, something is wrong, seriously wrong. I wrote team associated about it before I switched spur gears, just because I wanted the information on the spur and clutch setups. They warned me about overheating issues. They told me that the spur gear should get warm, but not hot. If so, there's most likely a problem with the slipper clutch.
Aslo, check something else. I don't know for sure, but check your clutch shoes lately? What shoes are you running? If you're running the stock teflon shoes, why don't you try a MIP Racing Clutch. I have one, and I have next to no heat on my clutch bell after heavy duty running. And I love the performance gain I got from it.

Just a few ideas.
Also, one other thing that just came to mind.. What setup are you running? Are you running high gearing? Stock? What tooth count is on your spur and clutch bell? If they are too high, it might be causing the clutch itself to slip more, causing an increase in heat, and producing you with this problem. The stock setup was a 15t clutch bell, and a 66t spur gear.
Originally posted by can-fly-but-not-drive
If the slipper and or dif is to tight I guess that will cause the bell to get hot too?
what
As for that, if the differential is too tight, yes it can cause an overheat, as I said before, with the clutch having to take the "weak" spot. Causing the slipping and increase in heat. Also, the slipper as I said before, will cause the same thing.
I better just put the settings so you know.
Slipper clutch for stock is to tighten the nut all the way down, then loosen 1/4-1/2 turn depending on terrain. Don't go lower, because it will cause sever slipping in the slipper, witch will end up causing problems with the slipper disc, such as overheating/melting.
Differential tightening goes this way. Tighten the differential bolt to the locking T-Nut all the way down, then turn out exactly 1/4 turn. After a single run do this again and make sure the differential is not loosening. If it is, try the steps again. And if it fails to hold correctly again, tear the differential down and find the problem. Some people say to loosen it 1/8 turn, first time I tried that, it ended up with a snapped differential bolt. So I followed those steps that Team Associated had on thier website, in which I just relayed them to you. Hope those help as well
Write back and tell me what happens after these idea's are worked with.
Good Luck, AoD