11 speed campy ergos & shimano cassettes

[wombatspeed]

First a disclaimer: I just responded to the other thread on 'Shimergos" that was all about 8/9/10 speed. I have a question about 11 speed compatibility and started this new thread. (Mods please combine with other thread if this is getting out of hand...)

The background: Getting a new cross frame built and now have to decide on shifters. I run campy shifters on all my bikes, some with full campy drive trains, other with 10 speed shimergo. My cross wheels are all shimano compatible.

the decision to make: should I buy 10 speed or 11 speed Ergos?

the question: Does anyone have first hand experience of 11 speed campy with either 9 or 10 speed shimano cassettes?

Campy and 9 speed shimano:
One of the best sources (http://www.ctc.org.uk/desktopdefault.aspx?tabid=3946) claims that you can just run the 11 speed ergo with an all 9 speed shimano drivetrain. From the numbers of shifter pull and RD parallelogram pull this should work well.

Or I can run 10 speed ergos hubbubed to 9 speed shimano cassette & RD like I have done for years.

Campy and 10 speed shimano:
Down the line I might want to use 10 speed shimano/sram cassettes (12-28 or 11-28)
There seem to be basically 2 options for this:
a) the Lennard Zinn option: 10 speed ergo, 10 speed shimano cassette and 10 speed SRAM RD.
b) 11 speed ergo, 10 speed shimano cassette, 10 speed campy RD (NOT the latest generation Veloce et al with the new parallelogram). see http://www.cyclingforums.com/t/485369/campagnolo-shimano-mixed-gruppos

has anyone any first hand experience with a) or b) or with 11 speed ergo with 9 speed shimano drivetrain?

Cheers!

PS: The 11 speed ergos might me more future 'proof' - IF the new shimano 11 speed has the same cassette spacing as 11 speed campy. What are the chances of that happening ;-)

[Dave]

I don't have any first hand experience with mixed drivetrains, but as a mechanical engineer, I do understand cable pulls, RD actuation ratios and cassette spacing.

Although many people claim it works, it's easy to show that a SRAM RD should not work well with Campy shifters because the Campy shifters don't have enough total cable pull and the pulls are not uniform, as required by the SRAM RD. The first five Campy pulls are only 2.5mm each and the SRAM RD needs 3mm.

The 11 speed ergos pull an average of 2.6mm, but are also nonuniform, starting with smaller pulls and moving up to large ones, toward the larger cogs. That should work with Shimano 9, because both Campy and Shimano use nonuniform pulls and Shimano 9 has been measured to average about the same 2.6mm.

The 11 speed shifters with 10 speed RD and Shimano cassette makes no sense. If the setup was all 11 speed, the RD would move 3.8mm per shift, with a cassette spaced at 3.95mm, so it would always lag. Using a 10 speed RD would only make things worse because it's actuation ratio is slightly smaller than an 11 speed, creating even more lag. What would reduce the lag slightly is my modification of the RD cable clamp bolt, that will slightly increase the actuation ratio, combined with the 11 speed RD.

http://forums.roadbikereview.com/components-wrenching/campy-10-rd-11-speed-drivetrain-160601.html

I expect that Shimano 11 speed will have a spacing that is very close to Campy, just because there is so little room left to play with, unless the rear dropout spacing is increased. From what I've read, Shimano may cheat a little and increase the hub width to 131mm.

[binouye]

You could use a Jtek Shiftmate #4 (http://jtekengineering.com/shiftmate.htm). I'm running Centaur 10 ergos and 9sp XT cassette on my monstercross with a Jtek, and it works well (a picture in the custom bikes section). While its a different # pulley on my Jtek, I don't see why it wouldn't work with 11/10 too.

[wombatspeed]

Thanks very much, Dave. That makes sense. Ultimately, if the mechanics of shifter pulls and RD geometry are close then it won't just work in practice but also in theory. Other set ups that work in practice (but not in theory) are probably more likely to be finnicky in the long haul.

I think I will get the 11 speed ergos and run them with a 9 speed Shimano RD and cassette until I have managed to ride my stack of 9 speed cassettes into the ground. In any event there is something to be said for 9 speed chains and cogs for cyclocross. Once I am ready for 10 speed I will try your RD mod - or jump straight to 11 as by that time Shimano 11 speed will be ubiquitous, I am sure...

Binouye, I have been running similar combos as yours for years, too. Just with the hubbub cable routing rather than the Shiftmate.

[kramnnim]

I used 11sp Ergos with a Shimano 10 cassette for a while, it worked okay. Not great, but usable.

[ludo]

I used 11sp Ergos with a Shimano 10 cassette for a while, it worked okay. Not great, but usable.

which RD did you use?
campa 11 speed?
which chain?
shimano 10speed or campa 11speed?

[Kontact]

I don't have any first hand experience with mixed drivetrains, but as a mechanical engineer, I do understand cable pulls, RD actuation ratios and cassette spacing.

Although many people claim it works, it's easy to show that a SRAM RD should not work well with Campy shifters because the Campy shifters don't have enough total cable pull and the pulls are not uniform, as required by the SRAM RD. The first five Campy pulls are only 2.5mm each and the SRAM RD needs 3mm.


SRAM road pulls are not 3mm, they are something like 2.7/2.8. Campy 10 is also about the same, because the derailleur moves less for given cable pull, but Campy 10 is spaced wider than Shimano 10. So it ends up being a wash and Campy shifters pull about the same as SRAM.

[kramnnim]

which RD did you use?
campa 11 speed?
which chain?
shimano 10speed or campa 11speed?

11sp RD, Shimano 10 chain.