What makes a clutch grind bad at engagement?

[indy_500]

This is not on any of my sleds btw. But, what would make a clutch grind when it engages?

 

[indy_500]

i'm thinking it's not balanced/aligned right

 

[rp7x]

grinding

frt motor mts shot / primary rubs on the bulkhead

 

[rmk4ever]

rounded off chain case gears & or chain to loose.