28 vs 32

Interesting post on an issue I've been considering too.  Gear ratios are highly subjective and depend on weight, strength, gradients, and fitness.  After much deliberation (as it requires replacing the whole srive chain), I reverted to a 53/39 on my daily ride, a Litespeed. Other bike has alwaya been  53/39.

The reason: I found that the with a  50/34 on  (+3%/-3% all day) UK roads, I was riding lower gears on the 50.  Hills where the 34 would be nice comprise <10% of my rides, so for 90%+ of the time so the 34 wasn't getting used at all - whereas replacing a worn 50 every year is expensive.  

Not wanting to change my S/C deraillieur, I'm interested in the concept of adjusting the B-screw to fit a 32.  I'll put one on my spare wheels this weekend and have a play.... thanks all! 

A 32 allows me to remain completely seated until it hits 15+%. Once I'm 16% and beyond it gets mixed in and out of saddle work depending on how my legs feel.

If you really want to tackle steep stuff but your legs aren't there yet then, as mentioned, try a crank swap to 40/28, there's no shame in spinning and it's less demoralizing than getting off.

As people have said weight and riding style are huge influencers. I like a hill and find I don't need a 32 on a compact until you get over 20% (I'm around 80kg). Interestingly though, a rather svelte summer carbon with 30/28 won't get me up my nearest 25% but heavier winter bike with the 32 will. I thought the bike weight would make both possible but it seems sometimes you just need the teeth...

Only you can answer if a 32 is for you

1) what's your fitness like?

2) how heavy are you?

3) how hilly is your local area?

11-32 works fine on a shortcage Ultegra derailleur but Make sure your chain is long enough so you can cross chain. I wouldn't recommend ridding it cross chained but these things do happen when your blowing out of your arse up a col. 52-36 with 11-32 I have tried briefly but wouldn't recommend cross chain was scary.

i choose my gearing based on where I'm going to ride. locally we don't have any climbs longer than 10 minutes so I can slog up on 52/36-11/28  if I'm traveling I look at where I'm going a decide then if in doubt 50/34-11/32  nothing wrong with big gears 

I had same dilemma, moving from a comfortable ti bike with a 32 to a racier alu with a 28. In the UK, the 28 is faster and I found no issues on 15% to 20% climbs. Now in Europe, I missed the 32 as the climbs are so much more sustained and if you're having an off day, there's no where to go.

get a 32, also you dont need to change your derailleur even if it is a short cage, just wind the b-screw in a bit, lots of tutorials on youtube. The biggest difference with a 32 is the ability to spin up climbs of 10% even when you are going really easy

I thought this was going to be about tyre width

I had 50/34 with 11/30 on my commute bike until recently I swapped out the 11/30 for an 11/28 when I made the switch to 105.

A 30t is significantly easier to push up a steep hill than a 28t. I would have chosen 30 or 32t had it not been for the fact I was using the components I stripped from my road bike before I sold the frame.

It depends on what kind of riding you are doing; as I only have one decent sized hill on the way to work, I can get up it with no real problems. My road bike has 52/36 with 11-28 and I find that fine cycling round the Mendips.

You should ride on your new chainrings for several months then see if you really need to upgrade from 28T to a 32T. With a GS (long) cage, you certainly can slap on a 32T cog with no issues and probably no b-screw tightening.

If you're a heavy rider say 85+Kg then a 32t Cass will be very useful on steeper climbs. Mechanical advantage around 12% with a 32t, I would say it would allow you to maintain same climbing speed over a 28t with an increase of 8-10rpm. I don't know if you're a climber who likes to grind or spin, but if you're asking about a 32t I assume you want to spin whilst going up hills.

Gear down as much as you need to get up hills comfortably.

I've got a bike with 50/34 with 11-32 Cass. It worked well for me to get up UK steep climbs but wasn't sufficient for me on alpine type climbs. I've made up a new mountain climbing bike with 40/28 crank and 11-40 Cass. This allows me to keep a high cadence for sustained multi hour climbs. Btw I weigh near 95kg