Bought a ´79 10th anniversary edition with a frozen engine. Took it apart, replaced a piston, the piston rings, bearings, etc, when I put it back together and on the frame I tried turning the engine over by spinning the rear tire. There are no spark plugs in it but the engine won´t turn. Is this normal? Don´t think it is. Did I put a one-way clutch in backward? Maybe something else? Any help on what to look for as I take it apart again (sigh) would be appreciated.