tamagawa

Hello,

I'm moving to Campy 11 (Chorus) from Shimano and thus have to put a Campy-compatible freehub body on my 2007 Ksyrium ES wheel. I've read that there are compatibility issues with Campy 11 and Mavic wheels built prior to August 2008, and that this can be fixed by using a spacer behind the cassette.

I happen to have a .5mm Mavic spacer. Does anyone know if this will do the trick?

Thank you!

DaveSSS 

I put an 11 speed cassette (11-25) on an earlier model Ksyrium wheel and there was no interference between the hub and cassette.

tamagawa

Thanks for the reply. Glad to hear you had no issues. I've actually placed the cassette on the hub and it seems fine, but the guys at my LBS tell me I need a spacer (which jibed with what I've read online). As to why, however, I'm a little fuzzy, as it was explained very quickly in Japanese and I couldn't catch everything. I think it had to do with how the derailleur and the chain lined up.

DaveSSS 

The largest cog on an 11 speed RD is only about 1mm further to the left than 10 speed. My RD cage has 4-5mm of clearance in the largest cog, so that is not an issue either.

Unless you find that the lockring fails to tighten properly against the smallest cog, I can't think of any other reason to need a shim. I don't know why Mavic would make the Campy cassette body any different than a real Campy hub. IIRC, both have the same 36mm spline length.

tamagawa

Yeah, it almost seems as though the spacer is merely for cosmetic purposes, to fill the .50-ish millimeter gap behind the largest cog. I took the bike and spacer into the LBS today and they popped it on, and it nicely filled in the gap. They said the setup would probably be fine without a spacer, but that Mavic recommended one. No mention was made this time about derailleur-and-chain alignment.

Though still a little mystified by this spacer business, it looks like I can forget about the issue and enjoy my new bike.

Thanks!

tamagawa

Not to harp on the subject, but I thought it might be worth adding that the person who brought this issue to my attention in the first place served as a mechanic for the Fassa Bortolo racing squad for a few seasons. He worked on Pinarello bikes and Campy during his stint there. Became buds with Cancellara, too, which is pretty cool.

He owns a small but thriving shop (that seems to attract a lot over men over fifty who only use Record parts), and when I visited to ask him about building up my bike, one of the first things he said was that I would need two things: a Campy-compatible Mavic freehub body for my Ksyrium and a spacer. It was that spacer comment that prompted me to do a little checking online, where I found a few -- maybe three or four -- references to the issue.

I ended up getting my bike built at another shop, as his waiting list was quite long. I'll be sure and ask him for more details next time I visit.