My in-law has a 78 or 77 KZ1000. The rear brakes lock up on almost every ride. He's taken it to a shop to fix it at least twice and it still locks up on him. I'm thinking it could be the rear wheel out of alignment but if that is not the case what else could be causing this? I'm pretty sure he had all new brakes installed the second time at the shop and it still does it. It's why I think it might be in the wheel.