BY:TECHPete JSChris Stucker
DATE:1996-12-13

Gear inches have long been used by cyclists as a way of "measuring" the size of the gear that they are using while pedaling. While the gear inch output might look like an arbitrary number, it's actual historical value is derived from the equivalent that this gear would have been if it was used on an old-fashioned "Penny Farthing" or "Ordinary" bicycle. The math is pretty simple:

(# teeth in front chainring/# teeth in rear cog) * actual wheel diameter

Back in the days of old, when a cyclist could go to his local bike shop and buy specific freewheel cog sizes and make up his or her own gear ratios, gear charts were pretty important. It could help a cyclist determine if he had any duplicate gears, and had fairly even steps between all gears, and a logical shift pattern. However, with the advent of cassette gearing, and 8 and 9 speed rear blocks, much of this is lost. Too bad.

---

So why is this gear chart the best? Well, it's more accurate than "standard" charts, which use 26" or 27" as rather arbitrary wheel diameter values. Wheel diameter values are taken to 4 decimal places, and gear inches are calculated to hundredths. Go on, give it a try!

URL: http://www.oocities.org/SiliconValley/7116/jv_gear.html

This page hosted by Get your own Free Home Page