Comments by "Jack Voss" (@jackvoss5841) on "" video.

  1. I had one of these when on Okinawa. A crude, simple, reliable bike. I bought it used in 1970, and the engine had piston slap that was easily noticeable. When I sold it three years later, it still had the same amount of piston slap. Its manual had a power graph that I’ve never seen anywhere else. In addition to the standard RPM range with torque and horsepower curves, it also had a curve indicating “fuel consumed per horsepower produced”. It was highest at idle and wide open, and bottomed out at the RPM where the torque curve peaked. I thought, “interesting”, but not much more than that at the time. A year or two after I bought it, I regeared the sprockets down so that at any given RPM and gear, road speed was 75% of what stock gearing was. This had at least two effects. A lot more fun in the dirt, and fuel consumption dropped! My first thought was, “What? Wouldn’t it burn more fuel at higher RPM?” Well, the answer is, yes, no, and it depends. I rode at the same road speed as before, and the engine was turning faster. BUT, now it turned out that at my speed, the engine was NOW turning at very near the peak of that torque curve. Not a planned thing; an accidental thing. My fuel consumption dropped about 40%! A very pleasant surprise. And, a very good lesson for recip engines. Courtesy of Half Vast Flying
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