[Zeke]

Wouldn't too high a tension be felt in resistance? IDK, I don't have a fancy bike. We used to run drive belts on enduro karts where the one speed clutch was on the axle. Not as much killer heat on an axle clutch. Ran them tight, but not banjo string tight. Tightness builds heat as well.

Then they deteriorate. I bet the sun had something to do with yours. Or, what do they call it, ozone and something called "double bonders?"