Which Rear Mech and Cassette on Mavic Crossmax 650b wheelset

Marvinman

I'm building up a 3t exploro gravel bike which is going to have a mavic crossmax sl pro wts mtb wheelset, which is 650b. Link here: http://www.chainreactioncycles.com/mobi ... prod140702

I've given my lbs a shimano ultegra 6800 11spd cassette (11-28) along with a short cage 11spd ultegra rear mech. They tell me that this wont fit as the cassette won't work on the wheel and I need a mtb rear mech and mtb cassette

I'm no expert but I'm not convinced this is right. the cassette will work with the rear mech normally and I don't think the cassette body on the wheel is any different to a road wheel version as far as I can tell.

Can anyone see why the cassette, rear mech and wheel wouldn't work?

Thanks in advance.

Can anyone think on why this wouldn't work?

whyamihere

MTB freehub bodies are different to 11 speed road ones - They're a little bit shorter, so an 11 speed road cassette won't ordinarily fit on. However, Mavic have had their own size of freehub body for a while, which has always taken 11 speed cassettes, but I'm not sure if they fit this freehub body onto the MTB wheels.

Best thing to do, if you have the parts there, is to try fitting the cassette and see if it fits. If not, there's things you can do, such as filing down the freehub body or machining the back of the cassette.

Nick Payne

11-speed MTB cassettes will fit on an 8/9/10 speed freehub as they have the same width cassette body as 8/9/10 speed cassettes. Because of the bracing angle of the spokes and the larger rear cog on MTB cassettes compared to road cassettes, the largest cog can overhang slightly inboard of the cassette body and the derailleur will still clear the spokes. My wife is running an 11-speed XT cassette on a 9-speed Dura-Ace 7700 hub without any problem.

However, AFAIK, Mavic freehub bodies will take 11-speed road cassettes, as their Shimano/SRAM-compatible freehub bodies have for many years been wider that those of other hub manufacturers, and they supplied them with a spacer that went behind the cogs when fitting a 9/10-speed cassette. Unless their MTB wheels are fitted with a different freehub body to their road wheels, an 11-speed road cassette should fit.

Marvinman

Thanks all a new lbs is on the case should be sorted this week. There apparently is a slow gut difference but nothing major

janm399

I'm in the same spot as the OP—3T exploro with 650b wheels, but also 700c, and I don't want to go dinner-plate for my cassette, so I'd like to stick to SRAM / Shimano road 11-30 range. I dug a little and it seems that Stan's Crest will take road 11 speed cassettes.

Anyway, OP, any word from the LBS?