Campag Short Cage maximum cassette

mistermatthew

Currently running a 50-39 with 12-26 cassette and short cage record derailleur. Changed chain and thinking of changinging cassette to as its a little worn. However I wouldn't mind changing up to either a 28 or 29 cassette, maybe 12-28 or 13-28 or 29, not too bothered about loosing the smaller cogs as i realistically can only spin them down hill.

Howver I was wondering does this cassette setup work with my short cage deraiileur? Anyone have experience running a similar setup?

doozerie

It depends on your groupset.

With my 1999 Chorus 9spd groupset the rear derailleur copes with a 13-28 (with a 53/39 up front) without any problems - well, one niggly "issue" is that the chain is so long to accomodate the 28 at the rear that 39-13 and 39-14 combinations are really out as the chain rubs on the upper jockey wheel.

With my 2010 Record 11spd groupset I checked at one stage and the rear mech can handle a 29 on the cassette though I've not actually tried.

mistermatthew

Running 2001 record 10 speed

Surveyor11

I have a Campag Athena RD, I think its range is 11-29 max, but would need to verify (there's a sticker indicting this on the RD - I think I've a 27 on the big ring on the rear cassette at the moment, but remember having the check this out for possible lower gearing for the Etape last year).

letape

mistermatthew wrote: »

Running 2001 record 10 speed

I think its only the latest version of 11 speed rear mechs that can handle the 29 rear sprocket.

I expect the maximum yours could be used with would be 27 (no more than that anyway).

doozerie

mistermatthew wrote: »

Running 2001 record 10 speed

From the 2010 Campag manual (page 45) it says that the max sprocket size for 10sp short cage is 26. There is no guarantee that the same spec applied in 2001 mind you, so that information is not definitive for your mech.

doozerie

Further info here, here is a snippet:

Campagnolo officially recommends various rear derailleur cage lengths for use with specific cassette and double or triple chain ring combinations. However, it is important to understand that any 1999 to current, Campagnolo 10 speed rear derailleur, will shift up to a 29 tooth cog and down to an 11 tooth cog. The problem you will run into is that the derailleur cage may not be long enough to take up all the slack in the chain for a wide range. Thus Campagnolo recommends using a short cage derailleur with a maximum cassette cog size of 26 teeth even though it will shift to a 29 tooth cog. Chain wrap or CW is a helpful concept to understand when you need to determine proper derailleur cage length.

The "chain wrap" that they refer to is also called "chain capacity" - its the difference (in teeth) between front chainrings added to the difference between the smallest and largest rear cogs. For a short cage rear mech they state a chain wrap/capacity figure of 27 (though the 2010 manual I linked to earlier states a capacity of 30), with some flexibility. My current 9sp setup has a chain capacity of 29, exceeding the stated limit by 2 - it works fine for the lower gears, but does mean that I can't use the 39-13 combination and the 39-14 combination is iffy too. I don't find that a problem if I bear it in mind, it would be a poor choice if keeping track of your gear combinations was tricky though, such as in a race.

mistermatthew

doozerie wrote: »

Further info here, here is a snippet:



The "chain wrap" that they refer to is also called "chain capacity" - its the difference (in teeth) between front chainrings added to the difference between the smallest and largest rear cogs. For a short cage rear mech they state a chain wrap/capacity figure of 27 (though the 2010 manual I linked to earlier states a capacity of 30), with some flexibility. My current 9sp setup has a chain capacity of 29, exceeding the stated limit by 2 - it works fine for the lower gears, but does mean that I can't use the 39-13 combination and the 39-14 combination is iffy too. I don't find that a problem if I bear it in mind, it would be a poor choice if keeping track of your gear combinations was tricky though, such as in a race.

ok if i'm reading this right then a 12-26 to a 13-28 would only add 1 to the chain capacity? ie. it is the difference between the large and smallest cog not the size of the large cog, presuming it's not greater than 29 that is the defining mater. So in probability, with perhaps a chain length adjustment, the cassette would work.

mistermatthew

mistermatthew wrote: »

ok if i'm reading this right then a 12-26 to a 13-28 would only add 1 to the chain capacity? ie. it is the difference between the large and smallest cog not the size of the large cog, presuming it's not greater than 29 that is the defining mater. So in probability, with perhaps a chain length adjustment, the cassette would work.

Also i have a 39-50 front chain ring rather than a 53 so that means i have been using a smaller amount of the capacity leaving me more for the cassette??