Yamaha 750 cc

The 750 Yamaha had 63 hp. from an engine which had an internal crankcase counter-weight to make the engine nearly vibration-free. The engine had been copied from British motorcycles, which all suffered from gut wrenching vibration from their forward slanted piston arrangement. The counter-weight worked quite well for vibration damping, but probably robbed the engine of 10 or more horsepower.

The author had a bike very similar to this one, a 1975 model with disc brake.

 

The author's bike was a 1973 with drum brake on the front wheel, but the color was the same. He used this as the patttern for George Lawrence's motorcycle.

Like the author's, George's bike had a fairing and a sissy bar, for which photos of an identical  setup are not available.