Campy SR and Potenza medium cage differences

[naavt]

As the title suggests, can someone point the differences between those 2 cages?

[Sjoerd]

This certainly isn't a thoroughly thought-thru answer from my side, but I wanted to pair a Centaur medium cage 11 speed derailleur with Chorus shifters only to find out they aren't compatible. Apparently it has something to do with powershift, it makes a Centaur derailleur (and possibly also a Potenza derailleur) only compatible with certain shifters. I thought I had found a relatively cheap way to using a 32T cassette but it wasn't meant to be.

[smokva]

I guess we are talking about 2015+ 11 speed systems here.
I'm not sure about cage itself, but I think they used different spring tension in SR/R/C vs Potenza so Ultrashift and Powershift worked only with it's designated derailleurs.
I don't know if the shapes of cages are the same and if you could put Potenza cage on SR while keeping original SR spring.

I use 2009 11 speed on my 3 bikes, and if there is interest I can check out compatibility between Record/Athena/Veloce10 cages for that generation of 11 speed.

[Bondurant]

Yes: as above r.e. the spring tension. I have tried a short cage Athena RD with Chorus Ultrashift shifters (both from 11 speed 2011 era). It worked acceptably, even well, for single gear shifts, but multiple shifts not so well. I would imagine - though did not experiment for long - that shifting precision would deteriorate over time. Different generations of 11 speed e.g. mixing the one of the above with 2015 era I don't know about, but differing cage geo would make shifting potentially a lot worse.

For a short term solution e.g. a mountain trip - what I tried could be a goer. What generation are you on naavt?

[smokva]

Just for note, on two bikes I have Athena longa cage RD with 1st gen Ultrashift Record and Chorus and it works flawless. But Athena, even though being Powershift, started its life as Ultrashift (anyone remembers Athena in 2010 being Ultrashift and Ultratorque?) so Athena derailleurs are perfectly compatible with 1st generation Ultrashift. Same thing is with 10 speed derailleurs which are compatible with 1st generation Ultrashift.
Where Powershift starts to deviate from Ultrashift is 2nd generation of 11 speed. They designed them with different shifter/derailleur spring tensions so that you can't use cheap derailleurs with fancy Ultrashift shifters. But as I said earlier, I don't know about shape of the cage and if you can use Potenza cage in SR/R/C with keeping original spring from SR/R/C.

[Sjoerd]

I guess we are talking about 2015+ 11 speed systems here.

Just for the record: my shifters are pre 2015.

[smokva]

Just for the record: my shifters are pre 2015.

Since you have 1st gen, I doubt Potenza will be compatible. If you need longer cage it would be best to use long cage from Athena, which is made for triple and is made for 1st gen 11 speed.

[usr]

Just for the record: my shifters are pre 2015.

Yeah, get an Athena derailleur or get post 2015 shifters, simple as that. Might even earn you some money, because stocks for pre-2015 11s are even more unavailable than post 2015 11s.

[smokva]

This site has still some pre 2015 11 speed derailleurs on stock...
https://www.condorcycles.com/collection ... erailleurs

Whoever has groupset from that gen I suggest to get one spare FD and one spare RD...Athena is still priced quite affordable.

[naavt]

Yes, post 2015 rear derailleur. In this case a Record EPS.

I had a medium SR cage on my previous EPS 11s rear derailleur but it was ripped off the derailleur hanger when a plastic bag went flying and entwined himself in the rear wheel spokes.

Now I see that the SR medium cage is hard to find (not available for imediate purchase and I was thinking if it differs from the Potenza one, or if it's only a difference in the bearings or so...

[robertbb]

On the HO labeled 2015+ medium cage derailleurs, the cages were 100% identical aluminium part for Potenza, Chorus, Record and Super Record.

Source: I pilfered a few Potenza HO rear derailleurs for my 11 speed Chorus spare parts stash and had a very close look/comparison.