!!sp 105/Ultegra rear derailleurs compatible with 10sp drivetrain?

[scharny]

So I need to replace my rear derailleur, but was hoping to grab one of the newer ones. Will a new 11sp 105/ultegra rear mech play nice with a 6700 12-30 cassette and 10sp chain, or am I out of luck?

[Cicli]

Nope, the derailier speed needs to match the shifters from 10 to 11 speed.

[Clancy]

Nope, the derailier speed needs to match the shifters from 10 to 11 speed.

By derailleur speed I assume you mean shifter cable pull ratio? Not sure what derailleur speed means.

If you install a Shimano 105 11 speed derailleur to use with Shimano 10 speed shifters and a 10 speed cassette, no reason it will not work fine as long as you set the low limit screw accordingly. I'd have to see how the new 8000 would install, but that might not even be a problem.

Not sure why one would over a 10 speed unless you wanted the 11 for a future build. Nothing to be gained in performance.

[oldpotatoe]

By derailleur speed I assume you mean shifter cable pull ratio? Not sure what derailleur speed means.

If you install a Shimano 105 11 speed derailleur to use with Shimano 10 speed shifters and a 10 speed cassette, no reason it will not work fine as long as you set the low limit screw accordingly. I'd have to see how the new 8000 would install, but that might not even be a problem.

Not sure why one would over a 10 speed unless you wanted the 11 for a future build. Nothing to be gained in performance.

11s shimano rear ders are not compatible with shimanon10s shifters.

[Kontact]

Nope, the derailier speed needs to match the shifters from 10 to 11 speed.

This is the correct information.

[Cicli]

By derailleur speed I assume you mean shifter cable pull ratio? Not sure what derailleur speed means.

If you install a Shimano 105 11 speed derailleur to use with Shimano 10 speed shifters and a 10 speed cassette, no reason it will not work fine as long as you set the low limit screw accordingly. I'd have to see how the new 8000 would install, but that might not even be a problem.

Not sure why one would over a 10 speed unless you wanted the 11 for a future build. Nothing to be gained in performance.



What I mean is a 11 speed rear derailuer wont work with 10 speed shifters. I dont know the cable pull ratio but they are not the same and wont work.

[Kontact]

What I mean is a 11 speed rear derailuer wont work with 10 speed shifters. I dont know the cable pull ratio but they are not the same and wont work.

He understood you, he just has the wrong information about 10 and 11 speed compatibility. Probably because 7 to 8 and 9 to 10 were compatible.

[Cicli]

He understood you, he just has the wrong information about 10 and 11 speed compatibility. Probably because 7 to 8 and 9 to 10 were compatible.

Yeah, then there was all that mountan hocus pocus. :cool:

[Clancy]

11s shimano rear ders are not compatible with shimanon10s shifters.

Well I stand corrected! I assumed since a 10speed derailleur would work with 9 speed shifters, An 11 would work with 10 speed shifters, setting limit screws.

What's the difference? Guessing cable pull?

[Kontact]

Yup, cable pull. It would be like trying to use a Sram derailleur with Shimano shifters.

[Marc40a]

So I need to replace my rear derailleur, but was hoping to grab one of the newer ones. Will a new 11sp 105/ultegra rear mech play nice with a 6700 12-30 cassette and 10sp chain, or am I out of luck?

Brother, I run that same cassette on my commuter, a steel tourer with a triple up front.

I actually recommend a 9 speed derailleur, the M591. It has more chain wrapping capacity than any 10-11 speed road derailleur that Shimano makes. It's the last of the great road-compatible/mountain long cage derailleurs. A true classic.

[cribbit]

I had a dream last night that all the major manufacturers agreed on standards for everything and going forward all parts would be interchangeable across brands.

I was so disappointed to wake up from that and realize it was just a dream.

[Kontact]

I had a dream last night that all the major manufacturers agreed on standards for everything and going forward all parts would be interchangeable across brands.

I was so disappointed to wake up from that and realize it was just a dream.

They have agreed on so many things that you can buy a frame and equip it with components from any company. Now you want them to check in with each other every time they redesign their index systems?

[cribbit]

They have agreed on so many things that you can buy a frame and equip it with components from any company. Now you want them to check in with each other every time they redesign their index systems?

Bottom brackets are a clustermuck. Everything else is pretty hard to make proprietary without being obtuse. What are they going to do, change which side is drive side? Have a weird angle required for the deraileur hanger? They didn't need to do anything to allow frames to be independent of groupset.

[Kontact]

Bottom brackets are a clustermuck. Everything else is pretty hard to make proprietary without being obtuse. What are they going to do, change which side is drive side? Have a weird angle required for the deraileur hanger? They didn't need to do anything to allow frames to be independent of groupset.

There used to be multiple pedal thread standards, shifter mounts, cable stop diameters, chainlines, hub widths, etc. Bikes are much more standardized then they were.

[oldpotatoe]

Well I stand corrected! I assumed since a 10speed derailleur would work with 9 speed shifters, An 11 would work with 10 speed shifters, setting limit screws.

What's the difference? Guessing cable pull?

The dimensions and geometry of the rear der is different requiring a different cable pull than what's on 10s(or any other speed) der...

Can be way confusing..throw in shimano and sram MTB stuff vs road..and it gets cloudier..throw in what manufacturer's say(some not accurate) and gadzooks!!

[Billybob62]

The dimensions and geometry of the rear der is different requiring a different cable pull than what's on 10s(or any other speed) der...

Can be way confusing..throw in shimano and sram MTB stuff vs road..and it gets cloudier..throw in what manufacturer's say(some not accurate) and gadzooks!!

A really comprehensive article:
http://blog.artscyclery.com/science-behind-the-magic/science-behind-the-magic-drivetrain-compatibility/

[Clancy]

A really comprehensive article:
http://blog.artscyclery.com/science-behind-the-magic/science-behind-the-magic-drivetrain-compatibility/

Thank you for that, brilliant article.

I knew some of this but no where near as detailed or comprehensive

[Kontact]

It isn't a bad article, but it gets some things wrong, like ignoring DA 7400 that also had a different actuation.

Cog pitch isn't always a set number. Campy cogs are not perfectly evenly spaced.

Derailleur ratio is also just an approximation - the amount of lateral movement per unit distance of cable pull isn't actually linear because the movement of the derailleur is an arc rather than a line. Some parts of that arc will use more cable than others, making the actuation geometric rather than linear.


The reason that there is as much cross compatibility as there is just comes down to how derailleurs are too similar in size to have wild variations in cable pull - the fixing bolt can only be so far or so close to the adjustment barrel. On Campy's first Syncho systems none of their derailleurs had the same actuation, so each group had its own set of index rings that went in the shifter to match the geometry of each derailleur and the number/spacing of the freewheel cogs.