Ahh , The Michigan Madman . Saw him match race the WM III in Tulsa in about 1970 . Don't know when he went to what is probably a clutch on the WM 5 , but the first 2 ran a direct drive in and out box . He had 2 crewman that would push him into the starting beam , pick the rear up with Tommy bars , and swivel an old style prop stand under the rear wheel . Potter would put the bike in gear , rev the engine to 4,000 RPM's , and as the old five light tree was between the last yellow and green he shoved the bike forward off the stand . The bike and rider disappeared in a cloud of smoke , and then he came shooting out . Pretty awesome .
One more Potter story . In the mid '60's racing the WM II , he was at a track in Ohio ( I think) , and at the end of his run he shut down the ignition . Unfortunately the engine Dieseled , and the bike just kept accelerating . That version employed a Norton Roadholder fork and drum brake . Potter said the brake scrubbed off about 10 MPH before burning up . He was still traveling about 150 , running out of run off area rapidly , with a forest about 100 yards in front . He had no option except to bail off , so he did . After tumbling , rolling , bouncing , and generally rag dolling for 70 yards , he came to a stop , only suffering some bumps and bruises . The drag bike was located some distance into the trees , completely destroyed after knocking down some 6" saplings . Of course shortly after returning home he began construction of WM III . Some folks never learn