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I've read that the Campy 10 shift/brake levers are compatible with Sram derailleurs. However, are the Campy 11 shift/brake levers compatible? Anyone tried it?
 

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doubt it

kma said:
I've read that the Campy 10 shift/brake levers are compatible with Sram derailleurs. However, are the Campy 11 shift/brake levers compatible? Anyone tried it?
I can't say I've tried it but the SRAM shift system seems to have a longer cable throw ("SRAM 1:1 actuation ratio ") so I am not sure that would work. Why would you want to do this??
 

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no...

Campy 10 shifters pull an average of 2.83mm of cable per shift, but that cable pull is not uniform. The first five shifts are only 2.5mm, the next two are 3mm and the last two are 3.5mm. SRAM shifters pull a uniform 3.1mm per shift, so even Campy 10 shifters are really not a good match with SRAM RD. I know that Lennard Zinn posted info about a Campy/SRAM setup but it makes no sense to me. It would take a Campy shifter 6 clicks to pull enough cable for 5 shifts of a SRAM RD. That's a major error.

The 11 speed shifters would be far worse since they only pull an average of 2.6mm per shift and those pulls are not uniform either.
 

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additional question

C-40 said:
Campy 10 shifters pull an average of 2.83mm of cable per shift, but that cable pull is not uniform. The first five shifts are only 2.5mm, the next two are .3mm and the last two are 3.5mm. SRAM shifters pull a uniform 3.1mm per shift, so even Campy 10 shifters are really not a good match with SRAM RD. I know that Lennard Zinn posted info about a Campy/SRAM setup but it makes no sense to me. It would take a Campy shifter 6 clicks to pull enough cable for 5 shifts of a SRAM RD. That's a major error.

The 11 speed shifters would be far worse since they only pull an average of 2.6mm per shift and those pulls are not uniform either.
C-40, since you seem to know these things, does Campy 9-speed also use a non-uniform cable throw pattern?
 

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DaveG said:
I can't say I've tried it but the SRAM shift system seems to have a longer cable throw ("SRAM 1:1 actuation ratio ") so I am not sure that would work. Why would you want to do this??
SRAM's 1:1 actuation ratio is used on their mountain bike components, not their road bike components. You cannot, for example, use their mountain bike derailleurs with their road bike shifters for a touring setup. The road bike actuation ratio is around 1.4:1, which is what Campagnolo used on their previous iteration of indexed shifting (pre-2001). Their cable pull at the shifter is linear so every shift pulls the same amount of cable for every shift, which is different than what Shimano and Campagnolo uses. Suntour was the only other company that I'm aware of that used a linear cable pull at the shifter but they spaced their cogs accordingly. Shimano (and SRAM, by default) use evenly spaced cogs on all of their cassettes and Campy's cassettes are almost evenly spaced. How does SRAM get away with it? They have that little linkage arm thing on their derailleurs that allows the derailleur to move the same amount for a given amount of cable pulled whether it is at the beginning or end of the throw, unlike Shimano, Campy, and Suntour indexing rear derailleurs, which move less as the derailleur moves closer to the spokes.
 

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Squidward said:
SRAM's 1:1 actuation ratio is used on their mountain bike components, not their road bike components.
The SRAM website states "When we launched our road technology from scratch we reapplied our MTB proven SRAM 1:1 actuation ratio (shifter cable travel : derailleur movement) for 10 speed rear shifting."

So...what gives?

Asad
 

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yes...

DaveG said:
C-40, since you seem to know these things, does Campy 9-speed also use a non-uniform cable throw pattern?
Both Campy and Shimano shifters have nonuniform pulls. Campy 9 requires more cable pull. In theory, it should average about 4.55/4.15 x 2.83 = 3.1mm. That average would be close to what's required by a SRAM 10 RD. There are two version of 9 speed shifters - those for RDs older than 2001 and one for 2001 and newer RDs. The older model pulled a little more cable.
 

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thanks

C-40 said:
Both Campy and Shimano shifters have nonuniform pulls. Campy 9 requires more cable pull. In theory, it should average about 4.55/4.15 x 2.83 = 3.1mm. That average would be close to what's required by a SRAM 10 RD. There are two version of 9 speed shifters - those for RDs older than 2001 and one for 2001 and newer RDs. The older model pulled a little more cable.

I have "old" 9-speed and I have always felt the RD was more senstive to adjustment than on my 10-speed systems. I would think that more cable movement would mean less finicky however, so I suppose that is not the reason
 

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derailleur wear...

Deraileurs get sloppy after many years of use. Although it's often said that Campy is rebuildable, there is no way to restore all of the small pivot points when they get worn. I noticed that my oldest Chorus 10 RD had developed a lot of wag down at the lower pulley if it was wiggled up at the top pivot where it bolts to the frame. The axial play had increased quite a bit over the years. This can be fixed with a home made shim washer placed behind the C-clip that holds the main pivot bolt in place. I first made a washer from some plastic that was .019 inch thick. That helped, put there was still more play that could be removed. I made another washer from .031 inch aluminum and it took all of the play out. There's probably not more than .002 inch of clearance left.

I just drilled a 3/8" hole in the shim material then used a dremel sanding drum to take it out to 10mm. I cut the material into a square to start with, then clipped off the corners to make an octagon. The washer doesn't need to be round.
 
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