I just had the shifting cables on my 2009 Kestrel RT900 with Sram Red replaced with Yokozuna Reaction Cables. I have never been happy with Red's shifting. I changed the chain to Dura Ace and the cassette to an Ultegra 12-25, which was a real improvement in terms of smoothness and noise. But the shifting remained kind of lackluster with the Sram cables. I changed them out once with new Sram cables, but still always felt something was not right.

Well, after reading a few posts around the internets and the incredibly well-written copy at Competitive Cyclist about the Yokozuna Reaction cables, I decided to give them a try. And all I can say is wow - what an amazing difference. Shifting is super fast and crisp - the difference is night and day. As Competitive Cyclist put it, "in nearly every way it's lived up to the hype." Really, for the first time since I bought this bike, which now has 4000+ miles on it, it just feels right. It's really transformed the riding experience. They weren't so easy to install - says my mechanic, the talented Rob Noti at True Blue Wrench Works in Carrboro, NC (http://www.truebluewrenchworks.com/" – who installed them – with the internal cable routing in the Kestrel frame. And the brake cables included in the kit didn't quite fit, but braking was not a problem. But Rob got them in and man do they work.

Anyway, enough gushing, but I just had to share. These cables just really worked for me - the best money I've spent on anything bike-related for a long time.

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www.bikehubstore.com

Does anybody know whether they can be used on a Cervelo S2 2012...?
How many kilometers can I expect to get out of them...?

Thanks!

Don't know about your cervelo, but I put these on my rain bike 2 years ago and about 15,000 miles ago. Still work great, but I do occasionally pull the rear der housing part off and clean and lube.
These cables are awesome as the op said.

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TIME RXR