General Cycling Discussion - Tell me about cassettes

What do the numbers mean in relation to the cassette, 12X25, 11x21 and so forth?
Are they basically the same deal as with cranks (39 x 53)

And how do you know what cassette specification is right for you?

12-25 cassette would mean a gear range from 12T to 25T.
the combination will differ from cassette to cassette, and is specified if 7, 8, 9, or 10 spd.

how do you know what's right? Well, if you ride more in the flats, and average more than 35kmh, I think the 11-21 is good for you. If your route has lots of steap climbs then a 12-25 would do you good.

Then again there was the 70's
Those weere called 8 tracks and then another came out called the cassette, it was more compact... :D

Then again there was the 70's
Those weere called 8 tracks and then another came out called the cassette, it was more compact... :D

I saw somewhere that the cassette predates the 8 track.

some people like the varied spacing that a 12-25 gives to you. of course not many drivetrains will allow you to ride in a 39-25 combo anyway, but....

i really appreciate the 11-21 (mostly flat, some rolling midwest) because when you shift your cadence doesn't get disrupted as much due to potentially larger changes in the cassette gear inch.

in an 11-21, the gear changes are not as noticable and are more fluid (if you are riding flat type terrain)

when you look at the gear teeth on the 11-21 cassette, there are more 'aligned' --> a well trained rider can benefit from even small changes in gear inch.

now no one would ride a 11-21 in the mountains.....

The 39-25 conbo isn't the problem, its a 53-25 that won't always work smoothly. I ride a 12-26 8 speed on widely varied terrain. Works great for me.

The 39-25 conbo isn't the problem, its a 53-25 that won't always work smoothly. I ride a 12-26 8 speed on widely varied terrain. Works great for me.

You're crosschaining your drivetrain, don't shift into that combination. That combination puts too much lateral stress on your chain.

gustaf,

you need to know who the manufacturer is and how many speeds your shifter/derailleur combo require. A Shimano-type is the most common type of cassette and many other manufacturers follow their specs. Campagnolo is another big one; the two are not compatible.

In terms of what kind of gearing you need, you'll have to take into account your own goals, physical shape, and your rear derailleur. You probably have a short-cage derailleur, which means the bigs cog it can handle is roughly 27T. As others have said a wider spread will give you a lower gear, but there is a larger jump between gears, which makes it harder to keep a steady cadence; a "tighter" cassette will do the opposite. An additional note: a triple crankset allows for both a cassette with tighter gearing as well as "bail-out"/climbing gearing due to the smallest chainring.

Personally, i use a 13-23. Almost a straight block with a decent low gear; i never use anything higher than a 13 anyhow, why bother. but i don't compete.

ps- good similar thread

http://www.bikeforums.net/showthread.php?t=44887

I saw somewhere that the cassette predates the 8 track.

I'm pretty sure that 8 tracks came first. However, they sound better than cassettes, much the way that the earlier 4 tracks sound better than 8 tracks. That crazy music industry!

Another vote for cassettes first. But they weren't used for Hi-fidelity... mostly portable players/recorders. Gawd I hated 8 tracks. Did anyone ever have a player where the tapes didn't slip and drag, and routinely get "eaten?"

Sorry, Gustaf. Hope you got your question answered. ;)

some people like the varied spacing that a 12-25 gives to you. of course not many drivetrains will allow you to ride in a 39-25 combo anyway, but....

Maybe I'm misinterpreting you, but I can't see any reason not to use the 39-25 combination, assuming the 39 is your inner or middle ring, and the 25 is your inner cog on the freewheel/cassette. You wouldn't want to use the 53-25 or 39-12, but the 39-25 sounds perfectly acceptable.

Ok, cassettes came first, in 1963, with the 8 track appearing in 1964. See it all in the Sound and Broadcast Technology Timeline: http://www.classicthemes.com/technologyTimeline.html