Can a Shimano 11sp FD be used with a 10 speed group?

[Exonerv]

Stuff you wonder while drafting...

As one of the biggest benefits of the Shimano 11 speed groups is the improved front shifting, could an 11sp FD be mated to a 7800 10sp group? Has anyone tried?

[CircuitHero]

Won't work. The pull ratios don't match up.

[oldpotatoe]

Stuff you wonder while drafting...

As one of the biggest benefits of the Shimano 11 speed groups is the improved front shifting, could an 11sp FD be mated to a 7800 10sp group? Has anyone tried?

No, shimano 11s Ders unique to their 11s shifters.

[kramnnim]

Has anyone tried? How much more/less cable does an 11 speed shifter pull?

I assumed the cable pull would be different but others say that it works.

[RacerJRP]

The cage is also narrower since 11spd shifters have high and low spd trim + a narrower 11spd chain. You can make just about anything "work", but i'd recommend against doing this.

[rburnham13]

The cage is also narrower since 11spd shifters have high and low spd trim + a narrower 11spd chain. You can make just about anything "work", but i'd recommend against doing this.

That, and the pull ratios are different. May move, but will feel horrible, and not really move the chain well. I second the "not recommended".

[kramnnim]

...but again, has anyone actually tried it? Long armed Campy derailluers work fine with older ergos, but the ergos have more clicks than Shimano...

[saab2000]

I have not tried, nor would I want to do so.

If the front shifting on the 9000 is such an improvement I wonder what's so special about the previous generations of Shimano equipment. The 9000 is about like my Record fronts, except my Record front derailleurs require no trimming. Actual shifting up/down/up/down is essentially identical in terms of quality. When set up properly they all work pretty well in my experience.

What's the problem with the 7800 front shifting? That's a serious question. I once rode some 6700 stuff on a ride and it was fine.

[Exonerv]

For clarification, 6800/9000 FD's have a nice short throw action that seems to contribute to quicker shifts. I run both 6800 and the older DA7800 and while both shift fine, the 7800 requires a longer sweep of the shifter.

As far as cage and chain width between 10/11 speed, those numbers are so close that I don't believe they would be the limiting factor. Also my 7800 shifters have both high and low trim.

It would be nice to know the cable pull difference...

There's a WW thread from 2013 that delves into this for Campy, and those who actually tried it found that it worked with great results.

Anyone have a spare 6800/9000 FD they'd like to contribute to the experiment?

[AngryScientist]

5800 FD is the same geometry and they can be had for dirt cheap for the experiment...

i think it would work OK honestly, though i havent actually tried it, i dont have any shimano shifters in service. i can tell you that a 6800 FD works excellently on a friction shifted downtube shifter though!

[Rob1519]

For clarification, 6800/9000 FD's have a nice short throw action that seems to contribute to quicker shifts. I run both 6800 and the older DA7800 and while both shift fine, the 7800 requires a longer sweep of the shifter.

As far as cage and chain width between 10/11 speed, those numbers are so close that I don't believe they would be the limiting factor. Also my 7800 shifters have both high and low trim.

It would be nice to know the cable pull difference...

There's a WW thread from 2013 that delves into this for Campy, and those who actually tried it found that it worked with great results.

Anyone have a spare 6800/9000 FD they'd like to contribute to the experiment?

I found these at some point and saved them for reference. Values are in mm.

Shimano 10 Road 2.3
Shimano 9 2.5
Campagnolo 11 2.6
Shimano 11 Road 2.7
Campagnolo 10 2.8
Shimano 8 2.8
Shimano 7 2.9
Campagnolo new 9 3
SRAM (Exact Actuation) 10 Road/Mountain 3.1
SRAM (Exact Actuation) 11 Road 3.1
Campagnolo old 9 3.2
Shimano 6 3.2
Shimano 10 Mountain 3.4
SRAM (X-Actuation) 11 Mountain 3.48
Campagnolo 8 3.5
Shimano 11 Mountain 3.6
SRAM (1:1) 9 Mountain 4
SRAM (1:1) 8 Mountain 4.3
SRAM (1:1) 7 Mountain 4.5

[commonguy001]

I'm running the opposite set up and it works ok but isn't perfect.

CX70 10 speed front derailleur with the R685 hydro 11 speed shifters.
If shimano ever makes a top pull 11 speed front D I'll change it out but it's fine for now.

[Exonerv]

Great reference!

Shimano 10 Road 2.3
Shimano 9 2.5
Campagnolo 11 2.6
Shimano 11 Road 2.7
Campagnolo 10 2.8

Hmmm...that 2.7mm cable pull might explain why Campy 10/11 can be made to work with 11 sp Shimano as both are within +- .1mm.

It's also interesting to note that 9sp Shimano cable pulls are within -.2mm

In this table, are the values consistent for both Front/Rear shifters? Or, do these values only apply to rear shifting?

[kramnnim]

Rear only, I think.

If you can use a bit of tape or something to mark the cable at the down tube cable stop, you could measure how much cable the front shifters pull... If 7800 and 6800 pull the same amount per click, it seems safe to assume the derailleurs have a good chance of interchanging.

Won't affect the lever throw, though, that is built in to the lever...

[Exonerv]

Makes sense...and a simple way to check. However, it's the shorter throw I'm after, so...it appears little is to be gained.

Will play with things next weekend...