Road Bike Question- 9 to 11 speed Shimano rear cassettes

I have been out of the tech in the cycling loop for some time. I have been riding the same Bianchi XL with Dura Ace, and a 9 speed rear cassette (11-25) for nearly 14 years or so.

Today, I just picked up a very lightly used Specialized Roubaix. It has all Ultegra with an 11 speed (11-34) rear cassette.

I was thinking of keeping my Spinergy (aero wheels with bladed spokes, not the four-blade blender wheels) wheels from my Bianchi and swapping out the wheels for when I sell my Bianchi, as I think the Spinergys will be lighter.

Before I tear everything apart or try to measure (and fail), has there been capability with hubs with the number of rear gears going up from 9 to 11 speeds over time? Or should I just keep the new wheelset (Fulcrum) as is?

 

11 speed hubs are wider. Shimano does make an 11spd 11-34 cassette to fit on 10spd hubs. I have no idea if you have that one or if it'll fit on such an old 9spd hub. It shouldn't take you long to try the swap to find out.

Your Roubaix doesnt have disc brakes, negating any chance of swap?

 

I don't know lately but I made the wrong stuff work together a long time ago by making a fancy spacer...

Take it apart and look

 

I bought a very lightly used Roubaix. Guy bought the frame and then built it up, Ultegra shifters and front and rear mech, with Dura Ace rim brakes. Now, he had a stroke and is out of cycling. The bike has been sitting for two years.

I'm cool with it as is. Sure, discs would have been nice, but whatevs.

PS- I did some more research on the wheelset, it's not all that bad so I won't care about not putting my Spinergys on. I ride 100% of the time solo now and just for time, not chasing any distance records. So, if the new wheelset is 0.005 grams heavier, I'll live.

 

Always good to be on a fresh set of wheels as they do wear out. Especially after 14 years, your Spinergys are probably tired.