I have an old Shimano WH-R550 wheel I use on the trainer. It currently has a 10speed freehub body to match my road bike, but my TT bike, which I intend to use on the trainer over winter, is 11 speed.
Rather than source a fresh wheel, I’m hoping to just get a new 11 speed freehub body. Can anybody suggest a compatible freehub body, or advise if this one would fit - Shimano Ultegra WH-6800-R Freehub | Freehubs | Wiggle?
Looking online, the fitting pattern appear similar on most Shimano hubs, but may be different sizes?
This site tells you how you can make a 10-speed cassette with 11-speed spacing.
The custom-machined cassette that site mentions still seems to be available, but for a trainer-only wheel you’re probably better off just buying a cheap 11-speed one used or from a super cheap generic wheel manufacturer.
You should be able to use an 11 spd cassette on your current hub. I never bought an 11 spd hub and just used Al my existing wheels. IIRC, you need to add a spacer behind the cassette, though.
Somewhat related: I bought a Zwift Hub, 10-speed because that’s what I have on my dedicated trainer bike. I very strongly suspect that they installed the 10-speed cassette without a spacer behind it, because a) there was a spacer included in a parts packet (so it wasn’t on the trainer), and b) i had to adjust my high/low limit screws on my derailleur about 1mm to the “inside” to get my shifting to work.
It wasn’t until I fixed my derailleur limit screws that I realized the issue was probably just that Zwift installed the cassette without the spacer behind it. No worries, because it was an easy adjustment and things work great now, but I wonder how many folks are going to get burned by the same thing and simply wonder why their bike just doesn’t shift well with the Zwift Hub when it worked perfectly well with their normal wheels.
Some newer 10-speed hubs are in fact 11-speed hubs, but most older ones are not. The splines are not long/deep enough. Most 11-speed cassettes are a little bit wider than 10-speed ones, and even if the hub itself has the same length, need longer splines on it.
(Which is why you need the spacer to put a 10-speed cassette on an 11-speed hub - it’s not the other way round.)
Aparently you can change the hub to take an 11-speed cassette by filing the splines out, but I have never tried.
The other option is that some 11-speed Shimano MTB cassettes are designed to fit 10-speed hubs. They ‘bulge out’, the larger sprockets sit slighty further toward the wheel than their mounting base. However, as the OP says they want to use their TT bike on it, I suppose an MTB cassette isn’t an option.
Ah, that’s a pain but I’m not surprised they’re not compatible Going to buy a smart trainer soon, was just hoping a 30 quid freehub body would tide me over for a wee while.
That only works the other way round (10spd cassette on 11spd body w/ spacer), this hub is definitely 10 speed, tried to put the 11spd hub on but there’s not enough room for the 11t ring to engage on the splines.
Going to buy a smart trainer soon, was just hoping a 30 quid freehub body would tide me over for a wee while.