Bicycle Mechanics - cassette sizing

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booninight11
01-15-13, 10:21 PM
Hey i have an old shwinn traveler and i am wanting to replace the rear cassette. its a 14-32 but the number of cogs on the rest of the gears do not match up. they are as follows 14, 15, 17, 21, 26, 32. just wondering if ordering your 14-32 would work. btw i have analog shifters. sorry if this is a kind of a dumb question im a bit new to this

pierce
01-15-13, 11:13 PM
is it a freewheel or a cassette? see http://sheldonbrown.com/free-k7.html

I'm guessing a freewheel because cassettes on freehubs were rather new when 6 speed was available.

pretty hard to find 6 speed anything anymore. if its a freewheel, you can probably put a 7 speed on there, and should shift just fine with friction..
dabac
01-16-13, 02:06 AM
You've got to realize what the tooth count means. It's not the change in numbers that's important, but the change in proportion. If you want the steps between the gears to be as similar as possible, the difference in tooth count has to change in relation to the number of teeth available.
14/15, a 7% difference
15/17 a 9% difference
17/21 a 8% difference
21/26 a 8% difference
26/32 a 8% difference

Sometimes you'll find cassettes/freewheels with an unproportionally big inner sprocket, sometimes referred to as a bailout gear. It's a trick, or a compromise between having nice and rideable close ratios for most of your riding, and a bigger overall range for the really tough bits.

If you got a triple front, you can often benefit from going to a tighter ratio at the back. Usually the smallest chainring at the front will still provide enough range for most kinds of riding.

Airburst
01-16-13, 02:15 AM
just wondering if ordering your 14-32 would work.

Bikeforums sells parts now?


btw i have analog shifters.

By "analog", I assume you mean that the shifters have no defined positions, or "clicks", for gears? If so, these are more usually referred to as friction shift levers, or sometimes non-indexed shift levers. Shifters with a click for each gear are referrred to as indexed shifters.

If you have friction levers, almost freewheel or cassette will work with them.