Anyone running the new Campag 12-30 cassette?

majormantra

I've used a 13-29 Campag cassette on my 10 speed setup with a short cage mech fairly successfully and I'm wondering if I might get away with using the new 12-30?

Anyone tried it? I'm well aware this exceeds Campag's specs, but they're often quite conservative about these things.

Cheers!

g00se

I'd be interested to know too.
By the way - do you have a pre-2011 10 speed (old logo) or a post-2011 (new logo) rear mech? The design is slightly different so what may work for one may not work for the other.

majormantra

The bike I'm thinking of has a short cage 2009 Centaur mech. (My winter bike has a 2011 Veloce medium cage, which is less hassle.) Any idea what changes were made to the mechs?

drlodge

Depends, what chainset are you using, compact or standard? Should work with standard, can't see it working with a compact 34-50.

g00se

The post-2011 rear mechs use the same parallelogram to the 11 speed mechs.

From the Campag docs, the older short cage mechs could only accommodate a 27 sprocket and had a chain capacity of 30. The new ones have a max size of 30 and a capacity of 32. See:

Old: http://www.campagnolo.com/repository/do ... -07-09.pdf (page 45)

New: http://www.campagnolo.com/repository/do ... _10_12.pdf

Saying that, I've heard the older short cage ones will take a 29 (which I'm looking to try for some hilly events next year) and have a greater capacity than that given - but I've no idea about it taking a 30.

majormantra

It's with a standard. I take it a compact would mean too great a variation in chain length? (I'm slightly confused by what Campag means when they refer to 'capacity' on their tech docs.)

g00se

Yes - capacity is the variation in chain length given in 'teeth'. so if you have a 50:34 at the front - there is a change of 50-34=16 which the rear mech needs to accommodate when changing ring. On the rear, a 13:26 has a variation of 26-13=13. So the mech needs to accommodate 16+13=29 teeth.

So for a 13:29 on a 50:34, you would need to have a capacity of 32. For a 12:30 on a 50:34, it would be 34.

The modern short cage can take up to a 32 officially. But is two short of 34.

(I have a short cage pre-2011 one which has a max capacity of 30 and I run 13:26 50:34 (cap = 29).


Saying all that though, the received wisdom is that a Campag mech can take 1 or 2 extra than stated. Maybe even more if you're lucky. That's because A, the Campag specs have erred on the conservative side. And B, you may have the perfect chainstay length which will have the chain perfectly fit over the big ring and biggest sprocket with the cage at it's fullest extent. The worse case will mean you have to have the best part of an extra two link of chain to fit and so the cage won't be fully extended and hence you've lost a bit of the capacity (nearly two teeth).

Does that make sense - it's a bit waffly.

You can use the park tools rigorous chain length calculator to find the ideal chain length - and if the ideal length is near exact to an inch or a very small fraction over - then you should get a couple more teeth in there.

majormantra

Thanks, that's really helpful. I'll report back if I try the 12-30, there's a good chance I'll give it a go.

rolf_f

g00se wrote:

The post-2011 rear mechs use the same parallelogram to the 11 speed mechs.

From the Campag docs, the older short cage mechs could only accommodate a 27 sprocket and had a chain capacity of 30. The new ones have a max size of 30 and a capacity of 32. See:

Old: http://www.campagnolo.com/repository/do ... -07-09.pdf (page 45)

New: http://www.campagnolo.com/repository/do ... _10_12.pdf

Saying that, I've heard the older short cage ones will take a 29 (which I'm looking to try for some hilly events next year) and have a greater capacity than that given - but I've no idea about it taking a 30.

My Ribble certainly is fine with 13-29. I even reckon it could handle 13-30. But 12-30 I'd need evidence for!

majormantra

Just thought I'd bump this up again, as I'm in the process of deciding what route to take in setting up my race bike (Scott Addict) for the coming season. Ideally I'd like to stick with my current 10 speed kit but to get the low gear I want I need either a 13/29 cassette (which loses a bit of top end) or the 12-30, hence my question last month.

I did the rigorous Park calculation mentioned above and it spat out a number of 53.84". Am I right in thinking that this means the 53/39 and 12-30 combination probably won't work? As I understand it I'd need 54" of chain but I'm slightly unsure if the rounding up means that pushing the capacity that far is asking too much.

My other option is to go 11 speed and get a 12-29, but that has its own problems...

g00se

Might be worth it. I tried a 13/29 cassette with a 50/34 chainset with a short cage 2009 centaur rear mech and it worked fine (full cross chaining and everything). That's a capacity of 32 (Campag spec is 30 with a max sprocket of 27).

In fact, there was still a bit of take up in the cage and clearance from the mech to the big sprocket - so I think it would have taken a 30 (though whether it would have taken that with a 12 too I don't know).

If you've got a 52/39, then that with a 30/12 is a capacity of (13+18) = 31 - just one over the official limit. With an ideal chain length 0.15" shorter than 108 links, adding that 0.15" will hardly take up much of the capacity so I reckon you're onto a winner in terms of the short cage working.

The only issue could be the range of movement needed to get from the 12 to the 30 - but with my Centaur, I reckon it'll fit over a thirty.

majormantra

Well, it's a 53 rather than a 52, but I'm verging on trying it. If they'd just do a damned 12-29 in 10 speed I wouldn't have this issue...

g00se

This might be a solution.

http://road.cc/content/review/10641-mic ... d-cassette

They do a 29-12 for about £35.

majormantra

It's a possibility, but I've read rather mixed reports on the Miche cassettes - not sure I want one on my best bike.

I suppose the sensible thing would be to get a compact but that's not exactly a cheap option if I want a nice one.