What causes this damage to the primary clutch?

I finally broke a belt. I was having to much fun drag racing and probably didn’t give it enough time between races to cool off. Anyways, I pulled the clutch cover off yesterday and what was left of the belt was paper thin shreds. After I cleaned it out, I noticed there were dimples wearing into the primary clutch. What would cause this? Is it ok to just put a new belt in it and ride on?

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