[Closed] Spare rear wheel options?

It'll need to be 12 speed but if you have two cassettes with different wear then the shifting could be a bit messed up. I had a spare wheel for a while and ended up swapping the cassette between wheels. It wasn't actually that much of a pain with the right tools. Overall it probably easier to swap tyres if it is only a few times a year. Just get well fitting tyres that aren't a faff to seat and inflate.

If you are tubeless then it's a lot easier to swap a cassette over than a tyre. That being the case, you'd need the same type of freehub.

Regardless of quoted dimensions there are variances in hub sizes - often enough to mean you'll need to adjust indexing when changing over. With practice this only takes a couple of minutes.

I have 3 wheelset for my gravel/tourer so I'm well used to swapping around.

It depends if you plan to swap the cassette over each time.

If you want to use the same cassette on both wheels, then the hub / wheel will need the right driver for your cassette (if it's a GX cassette, you'd need SRAM's XD driver).

If you don't plan on swapping the cassette (I.e. you'll buy a second cassette) then actually the new cassette and driver don't have to match what you already have, but would obviously have to match each other. So you could buy another GX cassette and XD driver wheel, or alternatively a Shimano wheel would work fine. You may run into issues with differential cassette wear rates as above.

Also, different hubs can have slightly different spacing between the cassette and frame, and the disc and frame. So you may find that you also have to re-adjust your gears and / or disc caliper when you switch wheels. If you bought exactly the same hub / cassette / disc this wouldn't be an issue. But honestly maybe just change the tyre twice a year?

Changing tyres sounds the route - so much for my "brilliant plan" as they say!

Changing tyres sounds the route – so much for my “brilliant plan” as they say!

FWIW I've more than one wheelset for each bike.

It's a 15 min job to swap out a rear wheel - and rather than buying cheap, buy decent.

Even if you have to swap the cassette and the rotor, in my experience at least, it's definitely a more repeatable and likely easier process to do that than wrestle with a tubeless tyre, especially with old dried up sealant on the bead which ends up refusing to seal.

I have 2 sets of wheels for my trail bike, which are swapped quite regularly. The casette wear is not an issue if they're swapped frequently, as they wear at an even rate.

One set has heavier tyres for trail center use in the summer and swapped to Mud spikes for the winter.
The other set has lighter semi-tread tyres (minion SS) for longer summer rides.

Both on Hope Pro4's with same size discs. They swap out in seconds and need no tweaks to indexing and calipers needed.