Sorry for the roadie content.

Road bike is currently fitted with 6700 10 speed Ultegra with 50/34 and i am finding the compact gearing no good for me living in Norfolk so was looking to replace the crankset.

I have also just purchased a 2nd hand Cotic X frame and forks which need a groupset.

I have seen that CRC are selling full Ultegra 11 speed 6800 for £549, with voucher, cashback etc, it would be even less.

So was thinking of purchasing the new 6800 for the nice bike and swapping the older set across to the Cotic X.

After my life story, the question is, does the new 11 speed fit on my old 9/10 speed hub (in that i know 11 speed MTB XX1 etc requires new hub carrier)?

Seems like a great deal if i don’t have to replace the 2 sets of wheels i have for the road bike.

Nope, 11 speed freehubs are longer, so you would need a new wheel(s)

In one word no

Cheers guys, i thought that might be the case.

Unless you’ve got Mavic wheels where I believe they are comparable.

Yep – you just leave the mavic spacer out.

Correct – on Mavic hubs that have the spacer you just remove said spacer. Otherwise you at least need a new freehub body (retrofittable to most decent wheels), or a new hub.

Unfortunately they are Hope Pro III wheels with Stans Alpha rims.

Not that unfortunate, you can get a Hope 11 speed body IIRC.

Hope don’t recommend using a cassette smaller than 28 on the 11 speed free hub, if converting from a 9/10 speed hub as a smaller cassette may contact the spokes.
This was told to me be hope when I rang them a few days ago.