Cyclocross - single chainring up front set up.

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View Full Version : single chainring up front set up.


geekpunk
11-02-05, 10:14 AM
I want to run a single 48 tooth chainring up front with an 8 speed in the back. I bought the new ring. Once I remove the 2 rings I have now, is it better to put the 48 on the inside or outside of the crankarm?


jfmckenna
11-02-05, 10:17 AM
48 is pretty big. Are you racing? If so do you have a mountain cassette on the back like 12x32 or something? If it fits on the inner my experience says to put it there.

jpearl
11-02-05, 11:12 AM
I checked out the single ring application kits on cyclocrossworld.com, and they all seem to designed so that the chain ring and guard mount on the outer ring, while the inner guard mounts on the inner ring, although all mounting is done with specially-sized bolts. There were also reccomendations for BB spindle length. You might want to ask at a LBS that knows the technicalities of cyclocross bikes before trying.


ApolloCVermouth
11-02-05, 05:45 PM
Put it on the inside this will put the ring closer to the center of the cassette and improve the chainline. You should probably put some sort of a guard on the outer chain ring position to keep the chain from falling off. A large chain ring with the teeth ground off works well. Some people make thier guards out of plastic. For some reason guards (or whatever they're called) are expensive. On the inside you can either mount another guard to 'sandwich' the chain or, a cheaper solution is to use a chain guide like a 'dog tooth' or a 'third eye' which attach to the seat tube. I use the front derailleur to keep the chain on on the inside. This adds a bit of weight but it works.

geekpunk
11-03-05, 01:53 PM
gotcha.

if I race (I said I would try one this year, but haven't had time to practice mounting dismounting too much) I will probably go 48x18 single speed.

the 48 x 8 speed is for regular road riding and triathlons (I know it's not ideal, but it's the best compromise for what I want).

Scott H
11-04-05, 09:07 AM
gotcha.

if I race (I said I would try one this year, but haven't had time to practice mounting dismounting too much) I will probably go 48x18 single speed.

the 48 x 8 speed is for regular road riding and triathlons (I know it's not ideal, but it's the best compromise for what I want).

If/when you decide to race your single speed with that gearing, be prepared to suffer like a dog. That's waaay to tall a gear for anything more technical than a crit on dirt roads.