Changing Cassettes

Page may contain affiliate links. Please see terms for details.
A

AndyxBennett

Well-Known Member
Hi all

I've recently purchased my first road bike, and I'm loving it.

I was thinking about changing the cassette from 12-26 to a 11-32, to make those long steep hills a little easier, and the down hills a little quicker.
(Note: the bike is equipped with Shimano Sora)

However after doing a little digging around on the t'interweb there is the suggestion that I may need to change the rear derailleur for one from a mtb.

I'm sure there are plenty of people out there who have changed their cassette's to 11-32, but did you have to change the derailleur as well ?

Thanks in advance

Andy
 
TheDoctor

TheDoctor

Noble and true, with a heart of steel
Moderator
Location
The TerrorVortex
Hello, good evening and :welcome:
IIRC Sora will cope with a 30T rear cassette according to Shimano. I'd be tempted to try it, and see what happens. Or go with a 30T cassette, which will definitely work.
I recently fitted a 12-32T cassette with a 105 rear mech, which is only rated up to a 27T sprocket. It's a bit noisy in bottom gear, but it works.
 
Nigelnaturist

Nigelnaturist

Guru
Location
Pontefract
I did that, and got an Acera MTB mech, gone the other way now though, went from 26/13 to 34/13, then 28/13 and 26/13 (original) and now its 11/24, and back with the Sora mech.
 
Cycleops

Cycleops

Legendary Member
Location
Accra, Ghana
I have done this on my road bike. You will need to change the derailleur, I now have a 105 on mine now. You will need a medium cage model to cope with the lowest (32t) cog. To get smooth changes the jockey wheel needs to as near the big cog as possible, but not too near, otherwise you won't get a good change as some have said. Cost about £40 for the Shimano 105.
 
Grayduff

Grayduff

Über Member
Location
Surrey
FYI......The Specialized Roubaix comes with Sora Standard fit 32 cog on the back:thumbsup: so i cant see there being a problem.
 
Nigelnaturist

Nigelnaturist

Guru
Location
Pontefract
Grayduff said:
FYI......The Specialized Roubaix comes with Sora Standard fit 32 cog on the back:thumbsup: so i cant see there being a problem.
Click to expand...
Depends on the model, mine is 2007/8 it wouldn't adjust to take a 32th.
 
Nigelnaturist

Nigelnaturist

Guru
Location
Pontefract
Grayduff said:
Yep you are right,,Sorry:wacko: Mine is a 2013 model that has a 9 speed cassette..
Click to expand...
It might have done 28th, I also make my own gear ratios, I can change the 24 to a 26 if I am going to wonder into some hills more than we have here (which so far has been never, but always an option) or even the 28, though 21 to 28 is a jump, but could try 19/23/28, but for me it more important that i have the 11th as I have a 48/38/26 chainset. which gives me a very usable range 28.5" to 114.8" compare with the 52/40/30 and 13/26 set up it had when I got it of 30.3"-105.2" my 26th gives me a lower range than the 30th did even with an 11/24 cassette but slightly higher middle and outer rings, I will use the 26th and 15/17 instead of 38 and 24 even though the gearing is much the same 26/17 is 40.2" and38/24 is 41.6" but it gives me the option of going lower, I don't view it as using a granny gear just the right gear for me at the time.
 
simmi

simmi

Über Member
Location
Auckley, Doncaster
I have a ribble alloy frame fitted with a shimano tiagra groupset.
I have 3 different cassettes.
12-23 which I use if I go east of home which is pancake flat.
11-28 which I use if I go North, hilly but nothing too steep or long.
11-32 which I have only used once when I tried a few hills in the peak district.

The 32 should not fit my bike but it does, sora and tiagra are very similar so I would say give it a go.

A further note is chain length, I was sure I would need a longer chain but this was not the case as chain became too long on the 11T cog.

I also changed my crank to a compact 34/50 from 39/52 now this did require a different chain length, 1 link shorter and also I had to lower my front mech.

The biggest problem with the 11-32 is the huge gap between most of the gears unless you do all your riding on very hilly ground the gain you get from the help with the hills will be more than lost on flatter sections as your cadence will be all over the place.
 
Rob3rt

Rob3rt

Man or Moose!
Location
Manchester
AndyxBennett said:
Hi all

I've recently purchased my first road bike, and I'm loving it.

I was thinking about changing the cassette from 12-26 to a 11-32, to make those long steep hills a little easier, and the down hills a little quicker.
(Note: the bike is equipped with Shimano Sora)

However after doing a little digging around on the t'interweb there is the suggestion that I may need to change the rear derailleur for one from a mtb.

I'm sure there are plenty of people out there who have changed their cassette's to 11-32, but did you have to change the derailleur as well ?

Thanks in advance

Andy
Click to expand...

An 11-32 cassette would be absolutelly horrible to ride with. If you need easier gears, fair enough, but wide ass cassettes like that have daft gaps leaving it much more awkward to find your natural cadence and being inefficient on the flat. You care going to have a nasty cassette regardless, but don't bother going with an 11t if you can avoid it, you are artificially extending the range beyond your needs.

There may be no such thing as a 12-32t, I don't know because I have yet to ever need such a dinner plate, but if there is, choose that over the 11-32t.
 
Nigelnaturist

Nigelnaturist

Guru
Location
Pontefract
Rob3rt said:
An 11-32 cassette would be absolutelly horrible to ride with. If you need easier gears, fair enough, but wide ass cassettes like that have daft gaps leaving it much more awkward to find your natural cadence and being inefficient on the flat. You care going to have a nasty cassette regardless, but don't bother going with an 11t if you can avoid it, you are artificially extending the range beyond your needs.

There may be no such thing as a 12-32t, I don't know because I have yet to ever need such a dinner plate, but if there is, choose that over the 11-32t.
Click to expand...
As I mentioned before, the 11t works well with my set up as I have a lower front set going from 11/13/15/17/19/21/24 with 26/38/48 front. I know I could get smoother gradations if I fitted a 9 or 10 sp but it's a cost thing, an 8 sp with maybe 19/21/23/26 or 19/21/24/28 might be an option by the summer.
Though I hardly ever use the 26/24 combination.
 
You must log in or register to reply here.
Top Bottom