I just got an awesome deal on a set of Easton EA90 SL wheels and I need to get a cassette for them. I am running an all 105 setup (5700) currently and was looking at the Ultegra 6700 cassettes. I was planning on getting the 11-28 (which is what my 105 cassette is) but I keep reading that the Ultegra cassette (11-28) is only compatible with the ultegra and dura ace RD.

Has anyone used the ultegra cassette with 105 RD successfully? Or should I just get another 105 cassette? I'm keeping my current cassette on the wheel I use with my trainer.

im pretty certain you can use 105/ultegra/duraace without an issue. the only thing id check is the length of your rear der. cage dictates how large you can go. I think a short cage max's out at 27 then you will start to rub.

Any Shimano or Sram 10sp cassette that your RD can handle should work. I use a 6700 on my Sram bike.

I've never tried it but several people on this forum have reported that shimano short cage RDs can handle 28t. It may take some fiddling with B screw.

That's what I'm confused about. I have the 105 (11-28t) and see no reason why the ultegra (11-28t) would not work. I'm just looking at the specs on the shimano website and it state the ultegra cassettes are only for ultegra/DA. Could this be more of a marketing thing?

yes it will work. the 28 tooth gear will not work on older 105 group 5500 or earlier.

That's what I wanted to hear. Thanks.

That's because you are a smart, logical individual.

if you already have an 11-28 cassette and it's working fine, i don't see how there could possibly be an issue.

shimano's tech docs also say you should only use shimano chains with shimano cassettes/other stuff, and that's total baloney. i'm sure they would rather have you buy an ultegra RD with your ultegra cassette, but for RD alignment/shifting purposes, all shimano 11-28 cassettes are identical as far as i know.

Shimano's stated claims of compatibility are because of the new shift ramp profile and assymetric chain style they first introduced on 7900 and then 6700. New 5700 does indeed have the new style ramping and assymetric chain so the compatibility is total.

Even still, you could use one of the older generation (7800, 6600, 5600) cassettes and it will still work... The shifts (especially under power) just won't be as quiet and smooth as if you were using fully compatible components.

Bottom line: 6700 cassette will work perfectly with a 5700 chain.

Proof: https://www.youtube.com/watch?v=wExkjmW6LnQ

This^



I also use an Ultegra cassette on a SRAM bike.

This setup is almost exactly what I have now. All 105, except for Ultegra 11-28 cassette. Works perfectly well. Go for it.

I run DuraAce cassettes with my Red components.

But, watch for some off brand cassettes. I tried a Recon alloy superlight 90gm cassette once. The thing just couldn't be configured to shift properly. The machining must have been off just a touch compared to SRAM/Shimano/Compag cassettes.

I took it to the LBS mech who is also a top masters racer (not reason to put that part in there..hahah)..anyway, he was determined to try and make it work...no dice. He gave up. We threw a DuraAce on there, bam, working perfect 5 minutes later.

So, in general Shimano/SRAM, no problems.