It happened to me. I was removing the clutch to replace the inner primary seal. The aluminum posts broke off while removing the hub because the hub was seized on the shaft due to spinning. I even broke my indy's hub puller because it was on so tight. I replaced the hub with a steel oem unit. The factory upgraded the design to steel. I was told not to use loctight because I may have trouble removing the hub again (if I had to). With a steel hub, the proper torque on the hub nut, and no more burnouts it shouldn't happen again.

The PO must have beat on my bike after he built the motor up. (stroke, bore, and cam)

 

The aluminum clutch hubs are known to crack in the keyway also. Years ago, the good folks at Zippers installed a reinforcing collar on mine.

 

Got a Barnett set-up, not sure if it's steel, good question probably not. I've heard of people using impacts on the hub and splitting it like a log. Knowing this **** does save the rear tire.......,somewhat.