Hi all,
Might be ressurecting my c. 2001 Monoc TC2 for my eldest, who's sniffing around road biking...
It's got Xenon 9speed, with a pretty racey/high cassette on the back - can't quite recall, but probably 23 bottom-end. I do know it nearly killed me climbing abround in the cambriains when I was in my prime!
Was hoping to swap in cassette with some easier/lower end spread for him.
Q is - allowing for the mech to be up to a few more teeth, are modern/available Campag 9 speed blocks going to fit that freehub?
From what I can find everything 2000-on is compatible, in the 9sp/10sp rnage, but would appreciate collective wisdom/definitive answer form RB.
Cheers!
OK, so ...
Contrary to popular Internet opinion, there's not a one word, or even a one line, answer here.
Xenon 9 RDs have the same geometry as 10s RDs, which mean that, of you want to increase the gear range, you can.
However, you will probably have to change the RD because the medium cage, which you may need, depending on how much you want to widen the range by.
Cages of differing dimension to fit the 9s RDs are around but increasingly difficult to find.
Changing the cage is basically simple for a mechanic but it will depend a lot on the the final customer, if they are doing their own work, as to whether they're confident (and dare I say, competent?) to complete the operation ...
Add to that, the fact that Campagnolo's quoted gear capacities, be it maximum sprocket size, maxiumum rear derailleur range or maximum overall range, tend to be conservative - they are very dependent on exact frame geometry and the exact design of the rear derailleur hanger as well as (sorry & again, no insult intended) the skill and persistence of the mechanic. The ranges that Campagnolo give are safe for frames and hangers that fit within the basic dimensional "envelope" that all three "main" manufacturers assume, when designing transmissions, with no caveats other than broadly competent assembly.
To maximise the available range, you will need a Veloce or Centaur 10s long cage RD.
This will not change (again, contrary to popular internet belief) the maximum size sprocket that you can use at the rear - but it will change the range, because if the dropout, say, allows you to use a bigger sprocket than Campagnolo using the "standard" dropout specs that everyone uses, allows a bigger biggest sprocket, you may need the extra chain wrap (which is all the difference a longer cage, of itself, makes).
Could you use an Athena <important edit>triple long cage RD with a 9s lever? Yes in theory - but even with a 10s chain installed, you will find potential problems when cross-chained with the chain able to jam aginast the edge of the the jockey cage - worse with a 9s chain, plus you may find issues with an even "acceptable" front shift, worse, the narrower the chain used.</edit>
All that said, you could (within the quoted specs) use a compact chainset (50x34) and a 13-29 cassette with a medium cage 10s RD with no significant problems. This is not a maximised gear range but for practical purposes, might well be OK.
On the other hand, if you fancy living dangerously, you might look at a long cage 10s RD (in order to get the chain wrap that you need) and run a 12-30 cassette or a third party 12-32 cassette, 10s. In some cases, the rear dropout and associated geometry will work OK - in other cases, it won't.
If the "drop" from the centre of the rear wheel to the centre of the pivot bolt of the RD is >/ =28mm, a 32T bottom is often OK if less than that, not - and if too much greater than that (in this context, beware extenders like Wolf-Links etc), you can hit problems with chain control when on the smallest sprockets.
Unfortunately, when taking gearing systems outside of the standards that are tested in the lab, then tested in the field by test riders (and, of course, ultimately, tested in the market), there is an element of "suck-it-and-see" but ... other people's experience is generally not a great guide. Their definitions of acceptable shift might not agree with yours, they might omit to sat things like "of course, I couldn't use 34 x 11 or 50 x 32" and you never know, unless it's direct like-for-like, there is no guarantee that the hanger & chainstay specs / overall frame geometry of their frame (all instrumental in what you can and can't get away with), are a good match for yours ...
For reference, I'm Campagnolo's lead mechanic in the UK and have worked with the brand in various roles, mostly technical, since 1997 ... as part of some of the work I do with Campagnolo, I have "pushed my luck", routinely - so have a fair idea (not infallable, by any means) of what you can and can't get away with ...
