Cassette compatibility

[nscrbug]

I'm thinking of swapping out my 12-25 cassette for an 11-28, because I really struggle with hill climbing with my current setup (50/34 upfront). My bike is fully equipped with Ultegra SL (6600). For the new 11-28 cassette, I was planning on upgrading to the Ultegra 6700...since I've seen a lot of good prices out there recently. However, on several online retail sites...I've been seeing "notes" in regards to the 11-28t 6700 cassette requiring a 6700 or DA-7900 rear derailleur. I wasn't really planning on needing to buy a new RD, so this was a bit of a surprise to me. NOT that I would be totally against upgrading my RD to 6700...I just didn't really budget for it. Can anyone out there confirm for sure, that this is the case?

[lo123]

I'm thinking of swapping out my 12-25 cassette for an 11-28, because I really struggle with hill climbing with my current setup (50/34 upfront). My bike is fully equipped with Ultegra SL (6600). For the new 11-28 cassette, I was planning on upgrading to the Ultegra 6700...since I've seen a lot of good prices out there recently. However, on several online retail sites...I've been seeing "notes" in regards to the 11-28t 6700 cassette requiring a 6700 or DA-7900 rear derailleur. I wasn't really planning on needing to buy a new RD, so this was a bit of a surprise to me. NOT that I would be totally against upgrading my RD to 6700...I just didn't really budget for it. Can anyone out there confirm for sure, that this is the case?

I'm running 11x28 with a Ultegra SL 6600 rear derailleur (short cage at that). No major problems. It needs to be fine tuned more frequently now, but my hubby does it for me . I'll probably eventually replace the RD, but it does work.

[Cataboo]

I'm running an SRAM 11-28 on my old ultegra 10 speed rear derailleur no problems.

[nscrbug]

Hmmm...interesting. But I think this compatibility issue is limited to the Ultegra 6700 11-28t cassette. I'm sure if I bought an 11-28t 6600, there would be no issues. But I figured, with the 6700 offered at a such a great price ($59 at Nashbar)...I would just go with that. So I guess my specific question is...is anyone running a 6700 11-28t cassette with a 6600 RD?

[redrhodie]

Hmmm...interesting. But I think this compatibility issue is limited to the Ultegra 6700 11-28t cassette. I'm sure if I bought an 11-28t 6600, there would be no issues. But I figured, with the 6700 offered at a such a great price ($59 at Nashbar)...I would just go with that. So I guess my specific question is...is anyone running a 6700 11-28t cassette with a 6600 RD?

I just got the 11-28T 6700 cassette a couple of weeks ago, and I'm using it with an Ultegra long cage derailleur from 2007 (not sure if it's 6600, though--can't find a model # on it, but it's definitely not a 6700). It works just fine. I've done a few hilly rides, and haven't had to have it adjusted yet.

[nscrbug]

I just got the 11-28T 6700 cassette a couple of weeks ago, and I'm using it with an Ultegra long cage derailleur from 2007 (not sure if it's 6600, though--can't find a model # on it, but it's definitely not a 6700). It works just fine. I've done a few hilly rides, and haven't had to have it adjusted yet.

Well...this is good news to hear! And I just realized that in my last post, I stated that I could just buy an 11-28t 6600 cassette - ummm, no such animal exists, so my apologies for incorrectly stating that. Looks like I will have to investigate this matter a bit further.

I'm fairly certain that I need a different RD in order to get this to work...because based on what I've been told by 2 different LBS's, my stock Ultegra SL 6600 rear derailleur does not have enough range to accommodate a 28 tooth (or even a 27 tooth) cog...I was told that I am "maxed out" on my RD with my current 12-25 cassette. And since I definitely need a new cassette (mine is worn - new chain is skipping)...I need to figure out what to do ASAP.