Thread: Gear Inches
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Old 04-22-20, 03:41 PM
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79pmooney
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Another visual for gear inches. Picture the old highwheeler or "ordinary". Those tall, almost one wheeled bicycles that preceded the "safety" bicycle that we ride now. 1880s.

Now, that front wheel gives a gear inch of its diameter. 6' wheel" 72 gear inches. (Roughly, the normal everyday gear of a modern single speed; 44-16.) You have a 22-32 (I'm guessing) for a low. 22/32 X 27 = 18.5". A small child's tricycle. High gear of (say) 50-12. 113" No man ever could straddle that highwheeler and ride it. (Now you know why the safety bicycle took off. Not only could anyone ride it but racers could go a lot faster! And short people could compete. Before, all racers were tall. And nobody had a high enough gear.)

I was raised on gear inches. For about 20 years they were totally out of style. Many in the bike world wouldn't have a clue what I was talking about. Those who knew looked at me like i just brought up a tyrannosaurus rex. GI is back in style. Thank you! (The one gear notation that includes wheel diameter.)
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