Its more than just gearing: you actually have to have the power to overcome the resisting forces. The faster you go, the more power you will need exponentialy. For example: It only takes about 40 HP on a bike to 100 mph, but it takes more than three times that to do 200 mph.

A good example is a Porsche 914. Its geared to do about 145, but it can't reach full rpm in the top two gears. Top speed is 112 mph, or 110 mph with headlights on. 109 if you have dual mirrors. In fact, in heavy rain the car won't even pull high gear. But, it does get 35 mpg at 70 mph all day long.
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james
Its not how fast you go...Its how you go fast.
MC21 Rothmans
RS250
RC31
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748R
Porsche (many)
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