's Forum Archives - Cyclo-Cross

Archive Home >> Cyclo-Cross(1 2 3 )

Gearing question: 34/48 pros/cons?(9 posts)

Gearing question: 34/48 pros/cons?sbornia
Jul 11, 2003 2:39 PM
Hello all - I'm just about ready to put together a CX bike, and am considering a somewhat uncommon drivetrain of 34/48 with a 12-27 cassette. I'll be using the bike for all-day rides that I'd normally do on a mountain bike, and would like to be able to spin (or grind) over most climbs.

Are there any drawbacks or other consequences I should know about before I put this combo together? I could see the chain dropping in certain circumstances, but wonder if there's anything else...

Thanks - Steven
re: Gearing question: 34/48 pros/cons?atpjunkie
Jul 11, 2003 6:03 PM
I run it (48/36 and a 48/34) but actually may drop big ring to a 46 on one rig. it's quite rare to need a 48x12 unless you have lotsa road riding in your plan. If you can pedal a 48x12 offroad you are most likely going faster than your cx bike can handle. Most cx courses lack long enough straighaways to need that gearing. It's why Pro's run 42 single rings.
re: Gearing question: 34/48 pros/cons?lvrvrs
Jul 22, 2003 11:54 AM
What crank and bottom bracket do you use? I've been wanting a 34T inner chainring but haven't been able to find a good crank that will support it.
re: Gearing question: 34/48 pros/cons?atpjunkie
Jul 22, 2003 5:56 PM
I run XTR. As a Clydesdale I feel more secure running MTB drivetrain in general. Adventure Componenets (AC) makes a forged XTR knock off that can be had pretty cheap. running Vuelta rings on that set and XTR on the XTR crank. (I have 2 bikes)
Any "standard" MTB crank...The Walrus
Jul 22, 2003 6:04 PM
...i.e., one with 110/74 mm bolt circle diameters. Older 5-arm LX, XT or XTR models are good. Race Face is another good choice. Or, better yet, go to and check out the TA Syrius 'cross crankset, which comes with 48/34 TA rings for $199.99. That's pretty tough to beat... They also have a Sugino crankset (with 48/34) which is $60 less, but correspondingly less swank.
...and there's alsoThe Walrus
Jul 22, 2003 6:08 PM
the old Shimano RSX crank, which was available in one incarnation as a double chainring setup with a 110mm bolt circle (pretty unusual); it was even supplied with 46/36 rings, which work pretty well for 'cross. These things turn up on eBay from time to time.
Jul 29, 2003 5:53 PM
if you can afford it,buy it!!!!!!!
Pros? Yes. Cons? No.The Walrus
Jul 11, 2003 9:00 PM
I run a 34/48 with a 12-28 on one bike, with barcons and (8sp) 105 on both ends. Never had the chain drop (yet). It's a good, "real-world" drivetrain.
thanks for the advice!sbornia
Jul 12, 2003 2:13 PM
thanks guys, the deed is done, bike ordered with 34/48. now i just have to be patient, which is a lot harder than deciding which components to get.