campag xenon and crankset questions

Xenon 9 speed levers will work with double, compact and triple.

What sort of BB and chainset is it? If it's also Xenon 9 speed, then it's probably square taper - but sometime you find Mirage UT chainsets used with Xenon levers. Whatever, to change to triple, you'll may need to change BB - as if it's square taper, you may need a different spindle length, depending on the BB shell size. See: http://www.campagnolo.com/repository/do ... -06-06.pdf

Using 10 speed cranks on an otherwise 9 speed system shouldn't hurt.

k3vinjam3s wrote:

g00se wrote:

Xenon 9 speed levers will work with double, compact and triple.

What sort of BB and chainset is it? If it's also Xenon 9 speed, then it's probably square taper - but sometime you find Mirage UT chainsets used with Xenon levers. Whatever, to change to triple, you'll may need to change BB - as if it's square taper, you may need a different spindle length, depending on the BB shell size. See: http://www.campagnolo.com/repository/do ... -06-06.pdf

Using 10 speed cranks on an otherwise 9 speed system shouldn't hurt.[/quot


I'm most likely replacing Bb and crankset as its and old machine and there's a little bit of play there.

As for the levers, is it an easy job changing it to be compatible with a triple?

They're already compatible - all left-hand levers (except the recent power-torque levers post 2011) are indexed to pull a triple. if you fit a double or compact, the mech just limits the lever to enough clicks to move two.

As they're Xenon, I'm assuming they're escape levers (they have a thumb button rather than a thumb lever)? If that's the case, then one press of the thumb button drops down to one smaller ring (which would take two clicks on the up-lever to move it back the same amount) - so trimming only works with the extra-fine clicks going up. If they're proper ergo levers, then the thumb lever has the same fine-indexing so you can trim using the thumb too.

It depends on what type of mech it is, short-cage or medium-cage (or even long cage). Measure the distance between the two bolts going through the jockey wheels.

For an older 9-speed mech, the short cage was only spec'ed to go to a 26. There is risk of strain to the mech trying to clear a larger 28 sprocket - dependent upon the length of the hanger. Many have run 28 or 29 though. For a triple you will need a medium or long cage, otherwise it won't be able to take up all the chain slack when you go from one extreme to the other.

You can see the official campag spec reasoning here - it's a bit out of date (as it's pre the new 2011 10-speed mechs which can take a lot more chain and teeth on a short cage):

http://branfordbike.com/articles/rear-d ... s-pg62.htm


The reason some bikes can get away with more capacity is whether the ideal chain length falls dead-on, or a small fraction over, a full inch. If it does, then the rear mech will sit at it's safe maximum extent on big-sprocket and big-chainring. If not, then you need to add an extra link to the chain and so can't use the rar mech at it's fullest safe extent. The Campag specs appear to take a worst-case scenario where the chain is just shy of a link and so you need to add another link and loose a bit of the extent of the cage.

You'll notice the guy says that these older short cage can take 29, not just 26, but the poster on here, 'velotech' I think - who's a Campag service engineer - says this may strain the mech to failure depending on the hanger length and the amount of time you use the big sprocket.

I ran a similar shape 10-speed short-cage rear mech on a Miche 12-29 cassette with a compact front when I took part in the Cheshire Cat - so that's even more chain capacity over a 13-29 and it works fine. I reckon it'll even take another link of slack if it needed to. So I was happy I didn't need to change the rear to a medium cage until I read velotech's post about the strain. However, I live in Norfolk so I don't often need to use that cassette - so, for myself. I reckon as an occasional tool, it's fine. I'm off to the alps next year - so rather than use that setup for an extended period, I think that's a good reason to buy a brand new bike with lots of shiny things on it....