We are now in the transition from 10 to 11 speed rear cassettes. Shimano is at 11 on their Ultegra and Dura Ace and will be next year on their 105 (if rumors are correct), Sram has it on the Force and Red and one has to believe will have in on Rival and most likely Apex for next year.
Most 10 speed hubs cannot be converted to 11 speed even with a new cassette body. Some can so you need to check with the manufacturer if you want to move to 11. Some 10’s already will work with 11 speed.
Our old R and M series hubs cannot be converted to 11 speed (one of the reasons I moved away from that hub maker).
Our current 11 speed hubs come with one spacer. If you have an 11 speed set up you don’t need it. If you have a 10 speed cassette you will need that spacer plus the one that normally comes with the 10 speed cassette (because the 10 speed cassette is narrower than the 9). If you have a 9 speed cassette you will need just the one spacer that comes with the 11 speed hub.
Of course, there is no way you will ever remember that and that’s why Al Gore created the Internet.
Benny and Jim are off tomorrow to visit their families over the holidays and we will be closed Thursday through Sunday. If you believe I can do the work of three on Wednesday you are sorely mistake but I will do what I can.
Thanks for reading – John Neugent
