Gear terminology (tall, long, short, etc)

richrock

Could someone please be incredibly helpful and help me understand something I've taken for granted on bikes for years?

What does all this gear terminology mean? Specifically: High and low gear - Low I would assume is inside front ring, biggest ring on rear. Or is it the opposite?

And the same for taller/shorter gears - what are these?

And finally - why is it all measured in inches? I was reading a review where it said the gear range was 122" to 33". There's me completely clueless reading this... :roll:

I've ridden bikes for longer than I want to think about, and want to finally put this in my brain. If there's a linky I could read that's in plain english that would be awesome.

Dmak

Small gears for spinning up hills.

Big gears for flats and going down hill.

Not sure about tall and short.

Some things in inches because it's difficult/awkward/needless to change vintage standards.

Giant Phil

Inches is defined as (Tooth number front/tooth number rear) x Tyre circumference in inches.

It indicates the distance the bike will travel with one revolution of the crankarms.

Hope this helps, Phil

richrock

@Dmak so this means high gear is the faster for downhill.

@Giant Phil - thanks, makes a lot of sense. No problems with inches, I was born just long enough ago to have learned both metric and imperial.

John.T

Giant Phil wrote:

Inches is defined as (Tooth number front/tooth number rear) x Tyre circumference in inches.
It indicates the distance the bike will travel with one revolution of the crankarms.
Hope this helps, Phil

Not quite right. It refers to the diameter of a penny farthing wheel that would go the same distance with one pedal revolution. See Sheldon Brown.
http://sheldonbrown.com/gloss_g.html#gearinch
To the OP. High gears and tall ones are the same thing. Big ring / small sprocket.
Low or short are small ring / big sprocket.