Mixing Shimano Ultegra 6600 and 6700 components


New Member
Jun 5, 2011
I'm building a triathlon bike at the moment and am on the drivetrain stage. Unfortunately I don't have the money to go out and buy a new Ultegra 6700 groupset, so I'm trying to get some second hand stuff on the cheap, mainly from eBay.

At the moment the plan is to go with the following:

Second hand 6600 STI shifters

Used 6600 front mech

Used 6600 short cage rear mech

New 6600 front crank

New 6700 brake callipers

New 6700 bottom bracket

New 6700 cassette 11-23, or 11-25

New 6700 chain

New cables to link the whole lot together

I'm wondering if anyone has any experience/opinions if the above will work?

I'm most concerned whether the 6600 STI shifters will play nicely with the 6700 brake callipers. I gather the cable ratio is a bit shorter on the 6700 STI shifters, so I'm concerned the 6600s will stop the bike abruptly and not provide enough modulation.

My other, lesser concern is if the 6600 rear mech will work fine with the 6700 cassette and chain?

Any comments would be greatly appreciated.

I thought that the most recent DA & Ultegra calipers used a slightly longer pull ...

  • by my reckoning, a shorter pull would lessen the amount of modulation ... AND, why would someone want that?
  • a longer pull would allow the rider to affect more modulation

If that is true ([COLOR= #808080]and, it may not be for the Ultegra 6700 calipers & levers[/COLOR]) that the most recent DA & Ultegra brakes have a longer pull, then while it is certainly not as severe a difference as between cantilever brakes & V-brakes, to have the same FINAL POSITION of the brake lever relative to the handlebars when the brakes pads are LOCKED against the rims, you will have to set the pads incrementally closer when the brake levers are not actuated ...

AND, consequently, you will loose some modulation.

Regardless, if there is a difference in the pull rate then why are you potentially creating a probem by not simply using a set of 6600/([COLOR= #808080]any other![/COLOR]) calipers?
Hi Nickldn, unfortunately 6600 STI levers and 6700 brake callipers are not compatible nor the reverse, although the right 6700 STI lever is compatible with 6600 RD.

Also, I believe that left 6700 STI lever is only compatible with 6700 FD
I've seen the Shimano compatibility chart and indeed the 6600 levers are not showing as compatible with 6700 calipers. But I'm wondering why that is, is it a cable ratio pull issue (which conceivably I could get used to and put up with) or is it something more involved/complex than that? I was wondering if anyone has tried the two parts in practice and could elaborate on their experience.
Originally Posted by KLabs .

Hi Nickldn, unfortunately 6600 STI levers and 6700 brake callipers are not compatible nor the reverse, although the right 6700 STI lever is compatible with 6600 RD.

Also, I believe that left 6700 STI lever is only compatible with 6700 FD

I don't recall there being a 'trim' function on the Dura Ace 7900 like there is on 7800 FD. One could assume that the FD plates have been redesigned to negate the need for this. Of course I'm making the assumption here that 6600 and 7800 and 6700 and 7900 are very similar or the same in design, which is often the case with Shimano's top two groupsets.

The RD will work fine.

Playing mix and match with 7800 and 7900 STI levers and brake calipers was interesting but not as bad as I'd imagined it would be but the result was not optimal. It certainly wasn't something that you couldn't get used too - a bit like riding with carbon rims and new pads - but you'll not end up flying over the bars either due to an impromptu endo.
OK I have taken your collective advice and sourced some 6600 brakes. I think it'll be easier than trying to muck around with 6700s.

My next question is regarding which chain I need. The Shimano compatibility chart implies the 6700 and 7900 chains do not work with the 6600 chainring, however these two chains have now been superseded by the 6701 and 7901.

Does anyone know if the 6701 and 7901 will work with a 6600 double chainring and 6700 cassette? Or would I be better off finding an older 6600/7800 chain?
BTW. If you opt for a set of Campagnolo shifters then you won't have to worry about the minutiae which you have been asking about ...

Also, Campagnolo 10-speed shifters + SRAM rear derailleur == [COLOR= #ff0000]10-speed Shimano indexing[/COLOR] ...

  • IMO, you should find that both FRONT shifting will be better with the Campagnolo shifters and ANY crankset than with anything other than Shimano's Di2 shifters & their highly optimized components ... and, I'm not sure that Di2 is better for anyone who doesn't have arthritis ... I've had better shifting using Campagnlo shifters + unpinned-and-rampless chainrings than with Shimano Ultegra 6500 shifters & ramped-and-pinned chainrings
  • I've also had better shifting with Campagnolo shifters + Shimano cassettes than with the same cassettes & Shimano Ultegra 6500 shifters

Just match the chain WIDTH to the rear cassette you are using.