Singlespeed & Fixed Gear - Gear Equivalency on Triple Chainring 24 Speed?

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dydst
07-11-07, 06:33 AM
Hi guys,

I know that lots of things depend on gear ratios, etc., so I'm looking for a very general answer here:

What gear, on a triple chainring 24 speed, would be ROUGHLY equivalent to a "typical" fixed gear/S.S. gear?

I'm trying to get a sense of how hard you have to pedal on a fixie/S.S. I'm looking for an answer like "approximately the second chain ring up front, and the third smallest chain ring in the back".

Does my question make any sense?

Thanks!

rm -rf
07-11-07, 06:46 AM
I have an easy road gear: 45 -18. That's 45 teeth on the front, 18 on the back. This is about 18mph at 90rpm. A typical fixed gear often comes with a 48 - 16. It's faster on the flats, harder to climb the hills, and is about 21mph at 90rpm.

45 / 18 = 2.5
48 / 16 = 3.0

So count the teeth on your bike. The cogs in the back will usually have the number of teeth stamped on them. Pick a pair, and do the division to get the ratio. So a 39 / 16 is 2.43 and 39 / 15 is 2.6 which are similar to a 45 -18 for instance.

These ratios are usually converted into "gear inches" I'll let someone else explain what it means. The 45 -18 is 66 gear inches, and the 48-16 is 79 gear inches.
dutret
07-11-07, 06:53 AM
Hi guys,

I know that lots of things depend on gear ratios, etc., so I'm looking for a very general answer here:

What gear, on a triple chainring 24 speed, would be ROUGHLY equivalent to a "typical" fixed gear/S.S. gear?

I'm trying to get a sense of how hard you have to pedal on a fixie/S.S. I'm looking for an answer like "approximately the second chain ring up front, and the third smallest chain ring in the back".

Does my question make any sense?

Thanks!

no you can gear your ss bike however you want. If you want 42/14 get 42/14.

Using your 42t middle ring up front people generally people seem to run gears that would be equivalent to 42/14-42/17 or between the 3rd and 6th cog on a 12-26.

Aeroplane
07-11-07, 06:58 AM
Count the teeth on your big ring. Around 50? Find a cog on the back that is around 18. Try the cogs above and below it as well.