Singlespeed & Fixed Gear - Cog ratios

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velo86
07-09-10, 11:25 AM
Hi, I'm fairly new to riding fixed so would appreciate some guidance...

I'm currently riding with a 45 tooth crank and 17 tooth cog - a ratio which is really good for me.

I've just acquired a 51 tooth crank and was wondering roughly what sized cog to use which will be similar to the ratio i;ve got at the moment.

Any advice would be appreciated.
Thanks!

moonraker
07-09-10, 11:30 AM
http://software.bareknucklebrigade.com/rabbit.applet.html
^Go there and start plugging stuff in. I don't know your crank arm lengths or tire/wheel size, but once you plug everything in it'll give you a list of equivalent gears.
dsh
07-09-10, 11:42 AM
twenty

adriano
07-09-10, 02:47 PM
i really use a 21.
RobertFrapples
07-09-10, 02:58 PM
45/17 = 51/x

(45/17)/51 = 1/x

51/(45/17) = x

x = 19.26666

19 is a bit taller, 20 a bit more lower.
hairnet
07-09-10, 03:13 PM
45/17 = 51/x

(45/17)/51 = 1/x

51/(45/17) = x

x = 19.26666

19 is a bit taller, 20 a bit more lower.

Maths be gone!
http://www.theboxset.com/images/reviewcaptures/1495capture_lotr104.jpg
velo86
07-10-10, 05:43 PM
thanks for the help - i'm now sorted!
Bone Machine
07-10-10, 08:53 PM
http://www.fixedgeargallery.com/resources/gearchart.jpg