Lennard Zinn makes a discovery

By Lennard Zinn

Zinn's bike. Look carefully and you'll see Campy shifters and a SRAM rear derailleur. Works fine.

Zinn’s bike. Look carefully and you’ll see Campy shifters and a SRAM rear derailleur. Works fine.

Photo: Lennard Zinn

NEWS FLASH: I put Centaur Ergopower levers on my SRAM Red-equipped bike and have been riding it happily ever since with nary a hiccup in the shifting. I have a SRAM 10-speed chain, SRAM Red chainrings, SRAM Red front derailleur, SRAM Red rear derailleur, and SRAM Red 10-speed cogset mated with the Centaur 10-speed Ergopower levers.

This means that Campagnolo and SRAM 10-speed road shifters, including their bar-end models, pull almost exactly the same amount of cable with each click.

So … ?

So what, you say? Well, this has ramifications for anyone trying to mix and match components for any of a number of reasons. For instance, this could be a godsend for those who have a Campy-equipped bike but want to to use all of the Shimano-compatible wheels and Shimano 10-speed cogsets they have lying around (and there are lots of these folks, because I get lots of correspondence from them, asking how to make the things work together).

Just get a SRAM rear derailleur, leave everything else the same, stick any Shimano or SRAM 10-speed cogset in as is, and the bike will work fine.

A close-up of the rear derailleur on Zinn's bike.

A close-up of the rear derailleur on Zinn’s bike.

Photo: Lennard Zinn

It also could come in very handy for someone who wrecks a DoubleTap shift/brake lever on a SRAM-equipped road bike while vacationing in Italy. In this day and age, they would be unlikely to find a replacement SRAM lever in an Italian bike shop, but it would be a snap to find a Campagnolo one. So they could just slap the Campy Ergopower lever on their SRAM bike without changing the derailleurs, chain, cogs or anything else, and they would be golden.

A time trial or triathlon bike with Campagnolo 10-speed bar-end shifters may seem limited by requiring the use of Campagnolo freehubs and cogs, when the world is awash with Shimano-compatible ones. But now, a simple switch to a SRAM rear derailleur opens up the possibility of using all of those wheels with Shimano 10-speed cogs.

This also raises the question of why the first pro teams racing on SRAM Force and Rival in 2006 (like Kodak-Sierra Nevada and Saunier-Duval) used Campy-equipped TT bikes for time trials, since SRAM was slow in coming out with its bar-end shifter. They could have equipped those TT bikes with SRAM and just stuck Campy bar-end shifters on them.

Who knew?

I should explain

For those who are still wondering what I am talking about, I should explain why this discussion of SRAM derailleurs and cogs with Campagnolo levers automatically pulls Shimano cogs into the discussion.

That is because the SRAM and Shimano 10-speed cogsets are completely interchangeable; the spacing is the same, they fit on the same Shimano 8/9/10-speed freehub bodies.

(OK, SRAM cogs don’t fit on the deeply-splined aluminum 10-speed freehub bodies of current Shimano Dura-Ace hubs, but this is a miniscule part of the total freehub market)

It is well known that a SRAM 10-speed cogset shifts perfectly on a Shimano 10-speed-equipped bike, and vice versa. But Campagnolo 10-speed cogsets have slightly wider spacing and do not shift well in either SRAM or Shimano 10-speed drivetrains.

I’ve tried other ways …

(I get letters from people claiming that their Campy system works just fine with only a limit-screw adjustment when they stick a wheel with an unadulterated Shimano 10-speed cogset in. I’m not buying it. I have tried that, and I find the shifting to be highly annoying and unsatisfactory. I also have not found a set of spacers for a Shimano cogset that makes it work to my standards on a Campy drivetrain, since the larger cogs on Shimano cassettes are riveted to cog carriers, so you can’t change all the spacing.)

And those would be his Campy Centaur shifters.

And those would be his Campy Centaur shifters.

Photo: Lennard Zinn

I have also discussed here in years past (all of the way back to 2002!) how you can use a Shimano rear derailleur with Campagnolo Ergopower levers and vice versa. The simplest and least costly way to hook up a Shimano rear derailleur to a Campy shifter so it will shift smoothly on Shimano cogs is to attach the cable to the opposite side of the cable-fixing bolt than intended. There are photos of this trick on the second link below.

For a simple solution involving an adaptor that you can by and install easily, you can use a Jtek ShiftMate. It appears that Jtek now even sells an adapter to allow the use of a Campy 10-speed shifter with SRAM RED derailleur and cogs.

I did measure the difference in cable pull between SRAM and Campy 10-speed shifters. Nine clicks of a Campy lever pulls 27.0mm of cable, or 3mm per click. Nine clicks of a SRAM lever pulls 27.9mm, or 3.1mm per click. Jtek’s adapter may adjust for this minuscule difference, but in my experience, it works perfectly with no adapter.

One final note: If you are interested in using 8- or 9-speed cogsets, here is a good summary of a number of methods of doing mixing and matching levers, derailleurs and cogsets.

Technical writer Lennard Zinn is a frame builder (www.zinncycles.com), a former U.S. national team rider and author of numerous books on bikes and bike maintenance including the pair of successful maintenance guides Zinn and the Art of Mountain Bike Maintenance — now available also on DVD, and Zinn and the Art of Road Bike Maintenance, as well as Zinn and the Art of Triathlon Bikes and Zinn’s Cycling Primer: Maintenance Tips and Skill Building for Cyclists.

Zinn’s regular column is devoted to addressing readers’ technical questions about bikes, their care and feeding and how we as riders can use them as comfortably and efficiently as possible. Readers can send brief technical questions directly to Zinn. Zinn’s column appears here each Tuesday.

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