Just went through the same thing with mine. After checking the usual I pulled the plugs and found I had a cylinder full of water. Head gasket. I could not turn mine in either direction due to the fact it filled the cylinder with the piston down.my 82 1100 locked up today. Its not the cams or belte. The motor wil turn about 1/2 turn in ether direction then locks tight. Anybody got and idea.
I bought an 82 that had that too. The PO got off at his exit and the rear wheel locked on him. It was the stator bolt had come loose. Back left side rear engine cover, 17mm nut cap was cracked from the bolt and rotor wedged against the cap, rotor was wedged cockeyed against the rear case. He must have turned the bolt lefty loosey with the spark plugs in.Check that the stator bolt hasn't come loose at the back of the engine
been there , done that, got the t-shirt :shock: