xfimpg

Okay, some context here... you're tired of dying as you're climbing hills, so you've decided to replace your 11-25 for an 11-32... or is it going to be an 11-34...?
Ratio and shifting wise (quality being equal for both), any advantage one over the other?

Thanks for your thoughts!
Mike

mtnbiker66

Well...the 34 will spin a little easier.

Cyclist30907654

However, the rotational inertia (due to the huge 34 teeth cog) will be increased by 0.1%, causing a .0006% decrease in efficiency.

cryptid01

My opinion is that the 34 will be lighter.

xfimpg

I just rechecked the cog specs, 28-32 teeth and 30-34 teeth jump, so not any difference there for shifting latency.

Thanks for the feedback. Looks like it'll come to price or the best deal... doesn't it always?

probable556

First of all, 11-25 is typically found on a road cassette. The low gear on a MTB cassette is usually 32 or 34.

What MTB comes with an 11-25???

xfimpg

This is for a roadie. I posted this question here in relation to the cassette size.

ghettocruiser

I had one of each sitting in the basement for months... next to my scale. I installed the 32 yesterday without weighing it. Thus, I cannot confirm or refute.

xfimpg

Hey, is that old BrickTop you got for an avatar? Great character.

M_S

Are you using a road rear derailleur?

xfimpg

Nah, going to a Deore LX or XT long cage.

ZeCanon

9 spd I assume? sram makes an 11-28 10speed.. not sure about 9. I wouldn't want the big cog leaps you'll find in an 11-32 on the road.

ed 

I've come close to ripping my frt. derailleur off and repl. it with a chain guide several times. The only thing that's kept my 22/32/BG with 11/34t setup is the few long rides that ended in a near vomit experience...the 22x34 ratio kept my legs moving and kept me on the bike for that last climb.

I'd go 34, but...I'm on a 32lb inefficient piggy.

Dannihilator

I'd go 32.

M_S

I used a 52/42 with 11-32 in back most of this summer. An odd setup, I know, but it seemed to work out pretty well. 'Course I had been using 7 speed previously so the gaps in shifting felt to be about the same. Currently my main ride has a 39 x 26 low gearm which seems adequate. Haven't done any ultra hilly 200 mile races or anything though...

To the OP I'd go for the 28 (as zecannon suggested) myself since you've also go the 34. That's a pretty low gear. Other than that, 32 I guess. The shifting will feel clunky either way compared to a standard road cassette, but that's just the price you pay for a wider gear range.

TheFlip

I vote 34

xfimpg

Thanks everyone, I appreciate all your feedback.