bangkok

Can anyone guide me in answer to these questions regarding single speed chainrings (130bcd):

+ can I use an "inner" chainring from a road bike (no pins/ramps etc)?
+ my chain is 1/2 x 1/8 ... is this compatable with 8/9/10 speed road chainrings?

Thanks!

jdms mvp

yes to the second question but i don't quite understand the first question

bangkok

Thanks much. To clarify the first question:

Road rings are labeled as outer/middle/inner ... per the position they occupy on the crank. The outer and middle rings have shifting pins/ramps, while the inner ring does not. In this regard, the inner ring seems just like a single speed ring.

So long as the crankarm and ring bcd size matches, can I use an "inner" road chainring as my single speed ring? I'm looking for a 34t or 36t single speed chainring in 130 bcd, and all that's commonly available are "inner" road rings.

Would the inner rings bolt to the crankarm spider in the 'outer' position ... so as to be a single speed ring?

BenATX

Yes, that is what I do and it works great... If the BCD is the same then you are good to go. I don't know if anything smaller than 38t comes in 130mm, though, because the bolt pattern limits how small they can be. Just be sure that you are not looking at the 110mm or 74mm options...

bangkok

thanks kindly! And noted the 38t ... I've seen that, and 38t will be ok for me.

MIN 

the short answer is yes. generally the inner position will yield a 41mm chainline when used with the original bb. 1/8" chain is compatible with 3/32" rings/cog but not vice versa.

https://www.sheldonbrown.com/chainline.html

Aldone

- Yes
- Yes, but it's a little bit noisy

chase.

if you're using a road crank and ring, there's no real reason not to use 3/32" cog and chain. there aren't any benefits to using 1/8" at that point; you should just ensure your chainline is good using spacers if possible.

tarckbear

you can only use a raod chainring on a tarck crank.

Build your own

The point of ramps and pins on outer and middle rings is to assist the chain when shifting from a smaller ring.SS/FG=no shifting, so your good.

P.S. 1/8 chain on 3/32 ring= no noise...at least not on any of my bikes.