Physics for gearheads..or why gear ratios matter

I drew one of those in 1980, when I was 12.

I also own one. Not quite the same design- it's in a Zuma 125 scooter.

Has a "variator", where a belt rides up and down in a pulley that looks too big for it, depending on speed and centrifugal force.

0-45 MPH is pretty quick.

Nothing pisses of a Harley guy like getting beat off the line by a 125.