sram force chainring

keithc440

Strongly considering replacing my 53T outer on a Sram Force crank for a 50T. BCD is 130. Can't seem to find them for sale though. Our they available ? Anyone recommend a source ?

pastey_boy

http://www.ribblecycles.co.uk/sp/road-t ... trochri450

mitchgixer6

Check out 'Spa Cycles'. They have a large selection of chain rings.

racingcondor

The difficulty is that usually a 50t requires a 110 BCD (i.e. a compact) chainset. The Stronglight ones above (also on dotbike) are one of the exceptions but even then you're limited to a 38 inner so if you're struggling up really steep hills you might still need to replace the lot.

The problem with 50/39 is that you'll overlap a lot of the gears.

http://www.bikecalc.com/gear_inches

For instance, put a 12-25 cassette and 39/50 chainrings into the bikecalc gear inch calculator and you can see that 39-18 is essentially the same as 50-23 so you have overlaping gears for about 1/2 the cassette. Are you sure you shouldn't just be using the 39 more?

keithc440

Thanks for the replies. I live in a relativley flat part of the world (Formby, Merseyside) and find a 50 / 39 combo that I have on my winter bike really useful. I use a 12- 23 cassette and find the 39 inner for the hills around Parbold and Ashurst Beacon fine (Bank Top is a bit of a beast though on the 39 - 23). Often the wind is my main enemy and with the 50 I find I can bash in to it with a better chain line than on the 53. Yes I probably should use the 39 a bit more but my ego likes to use the outer ring.
Doing a bit more research I think the SRAM powerglide.chainrings are made by Truvativi. Struggling to find a source though. I expect the strongling rings would be just as good though.

pastey_boy

keithc440 wrote:

Thanks for the replies. I live in a relativley flat part of the world (Formby, Merseyside) and find a 50 / 39 combo that I have on my winter bike really useful. I use a 12- 23 cassette and find the 39 inner for the hills around Parbold and Ashurst Beacon fine (Bank Top is a bit of a beast though on the 39 - 23). Often the wind is my main enemy and with the 50 I find I can bash in to it with a better chain line than on the 53. Yes I probably should use the 39 a bit more but my ego likes to use the outer ring.
Doing a bit more research I think the SRAM powerglide.chainrings are made by Truvativi. Struggling to find a source though. I expect the strongling rings would be just as good though.

The Stronglight Zircal rings are much better than the Sram/Truvativ rings and will last much longer. TA do a 38 tooth inner 130bcd that will fit your set up.

pkripper

Why not change the cassette?

ricwilliams

keithc440 wrote:

hills around Parbold and Ashurst Beacon fine (Bank Top is a bit of a beast though on the 39 - 23).

dont forget clieves!!!

keithc440

I like a nice close ratio on the cassette. If I lived somewhere hilly yes a 12 - 25 or 12 -27 would be useful.
Its the top end 53 -12 I don't need.
Thanks for the advise on the stronglight rings. They are not too expensive so it may be worth an experiment.


Clieves is on my regular training route Ric.

racingcondor

I can't blame you for liking a 12-23 and that will help with the gear overlap I mentioned (if probably only 1 cog worth). My advice, learn to love your 39 and spinning. It's not hard to hold 25mph on 39-13 with a little practice so it's that big ring you don't really need ;-).

(yes I ride a compact)