Support road.cc

Like this site? Help us to make it better.

forum
road.cc bike forum

Compact chainset recommendations

by Mooman16
Sat, Jan 07, 2012 18:57
6

Hello,

I bought a Forme Rapide as a winter training bike with a compact chainset. Overall I am well pleased with the bike, but I'm have a lot of problems getting used to the chainset.

On my summer bike, I have a triple 105 setup (30, 39, 50), although I hardly ever used the 'granny' ring. I normally got along fine with using the 39 on the lumpy stuff and the 50 for flats and descents. There lies my problem however. On my compact setup, I find that my cadence rate has had to increase substantially when using the 34 to keep up with the group. On cycle runs up to 70 miles, that feels just too hard to sustain. Using the 50 just isn't feasible all day either.

Should I trade up to double chainset, or will I eventually get used to the compact chainset, if I put in enough miles? Cadence and fatigue issues aside, it's just plain embarrassing getting dropped, when I was able to stay at the front most of the time on my triple set-up!

I appreciate any and all advice from anybody who has dealt with the same issues previously.

Thanks!

Mooman

If you're new please join in and if you have questions pop them below and the forum regulars will answer as best we can.

Add new comment

6 comments

Avatar
msw | 12 years ago
0 likes

You might find it difficult to get hold of a 39t chainring with the same bolt circle diameter (BCD) as your compact cranks. They are usually 110mm I believe. As mentioned above you can get a 36 though and this is what I have - a 50-36. I also prefer it because I have to double-shift less, and can sometimes just shift the front. You could even go to a 48 on the outside too.

Finally I'm sure you're aware of this but I have killed many hours at http://sheldonbrown.com/gears/

Avatar
Mooman16 | 12 years ago
0 likes

Hello,

I should have mentioned that I am on an 8 speed cassette (12-21). I had hoped this would work ok when on the 34 chain ring (used more often that the 50), but I am worried about crossing too much.

Based on your feedback, here is what I have resolved to do:

1: Get back out on the bike for the next week or so and follow up with some sessions on the turbo to see if that makes things any better

2: If number 1 fails, go for a 39 chain ring and experiment with both the 12-21 and a spare 12-25.

3: Keep pedaling!

Many thanks to you all for the really useful info!

Mooman

Avatar
CyclistAtLarge | 12 years ago
0 likes

As I see it, there are three good options.

1) Different cassette with a bigger spread. 11-27/28, if one is available. (I have a SRAM cassette with that spread, but I don't know about Shimano's ranges or if the SRAM cassette would be compatible.)

2) Different small chainring. Find a size you like.

3) Change nothing, but get stronger. There should be nothing preventing you, in practice, from continuing with this setup. You might need to crosschain a little, but a hard winter of training like this might really pay dividends come the spring. Winter is a good time to work on this sort of stuff. Talk to your group, tell them what's going on, and make sure you know the route. I'm sure they'd be willing to stop every once in a while if you get dropped.

I prefer option 3, but I'm a bit of a glutton for punishment. (CX is my main discipline; I don't remember what it's like to do a ride without suffering. :P)

Avatar
Fringe | 12 years ago
0 likes

or you could change the 34T ring for a 36, or 37, or 38 etc etc

(spacycles sells TA ones in every conceivable number of teeth)

Avatar
TheOldCog | 12 years ago
0 likes

50/34 with a 12-27 on the rear or an 11-28 (10spd)

I ride the hills in Valleys of Wales on my compact and it always has a low enough gear, likewise it seems sufficient to hit the high 40's mph without spinning out.

If your running 9spd then you could change to a longer cage mech and run a MTB 9spd rear cassette - though I'd do some research first to find who else has done this and what works with road shifters etc.

hope this helps

Avatar
the_mikey replied to TheOldCog | 12 years ago
0 likes

On my 9 speed bike I use 34/50 on the front, I used a 11-32 on the rear with a MTB derailleur , I use a 9 speed shimano XT derailleur in bottom normal configuration so the gear shift lever acts in reverse, but it doesn't take long to get used to it.

On my 10 speed I use compact 34/50 and 12/28 on the back, no problems.

Latest Comments