Can I use the Campy 12-29 cassette on a 11s 50/34 compact setup?
Thanks for the info and the Campy link. I looked on the Campy site first but somehow did not find itAny Campy RD from the last 15 years will handle a 29T cog. Campy specs in any particular year are kind of meaningless because they simply specced the max cog as the max they made that year. Nothing to do with real max. You need to read the instructions and back out the "H" screw for clearance as necessary. (Campy max cog specs are in a way, worse than meaningless, but plain misleading. By saying one year the max is 26, and another the max is 29, the implication is that there has been some change to the RD when this not the case. Even today when the geometries of the 10 and 11-speed RD's are the same, the 10 lists 30T max and the 11 lists 29T. Again the "max" is the max cog they offer. Nothing to do with actual max).
A short cage will just handle a 33T wrap, but you need to be careful with chain sizing. Using a quick link make this process easier with trial and error. Normally you should use the small-small method, but in this case it's safer to use big-big and have the RD at it's max safest stretch.
The official word is here http://www.campagnolo.com/media/files/035_259_Technical%20manual%20-%20Mechanical%20units%20rear%20derailleur%20-%20Campagnolo_Rev01_02_15.pdf