Kickr Freehub swapping

[JMeinholdt]

I have a Kickr Core, which I assume is similar to other kickr models when it comes to changing out the free hub.

I have both an AXS bike and a Shimano 11 speed bike. In addition, both kids and my wife also use the trainer and have Shimano 11 speed. I really want to be able to use both of my bikes and my AXS bike more (the "hang loose" RD on my Exploro is awful for setting up on the trainer).

Setting aside that I'll need an XDR free hub and another cassette for it, how long will it take to swap cassettes and freehubs? I would likely be doing this 2-3 times/week over the winter indoor season. Is this a 10 minute job? 20? 30? Should I just forget that thought and stick with the Exploro on the trainer?

[1415chris]

Is using Erg mode an option for you? That way you wouldn't have to change cassettes, just couple of trimming clicks on your axs levers.

[JMeinholdt]

Is using Erg mode an option for you? That way you wouldn't have to change cassettes, just couple of trimming clicks on your axs levers.

I've thought about this. And this is probably a good option for dedicated workouts. My concerns would be wear on the flat top chain and/or the cassette due to the change in design. Second would be that I still wouldn't be able to do free rides and racing. I suppose I could give it a shot and just save the racing for when my Exploro is on it.

[hlvd]

It's only a ten/fifteen minute job once you've assembled the tools, spanner, lock ring tool and chain whip and have done a couple to refine your technique.

Plus you need to add taking off the rear wheel of the bike going on and putting the back wheel on the bike coming off otherwise you can't store the spare bike without risk of damaging rear mech.

Personally it's not something I'd be wanting to do two to three times a week as there are enough things to do already with sensor wake up, pairing, drink, headphones etc and even more things might put me off.

[MayhemSWE]

That all sounds like a huge hassle to me. Swapping things out that many times a week, it is only a matter of time before you're in a hurry and start doing things too quickly, crossthreading something or slipping with the wrench and damaging the axle end cap. (I did the latter the very first time when I swapped to XDR on my KICKR…)

If I were in your scenario, I'd buy one of the Chinese 12 speed cassettes that fit on a HG free hub. Then at least all you'd need to swap is the cassette and maybe do some fine tuning of your AXS derailleur. I hear they shift well enough even with AXS and flat top chain. Or buy a second trainer...

[ghostinthemachine]

You'll get fed up with it after a couple of weeks.
I got fed up just swapping cassettes (old turbo bikes, one 10, one 11)

Converted the 10 speed bike to 11 just so i would not have to swap another bloody cassette.

(Then another trainer turned up a few weeks later...)

[JMeinholdt]

If I were in your scenario, I'd buy one of the Chinese 12 speed cassettes that fit on a HG free hub. Then at least all you'd need to swap is the cassette and maybe do some fine tuning of your AXS derailleur. I hear they shift well enough even with AXS and flat top chain. Or buy a second trainer...

I'm afraid 2020 would claim another life if I bought another trainer at this point...

But I think the HG compatible 12S Chinese cassette may be a fun experiment... considering I can pick one up for about the same price as an XDR freehub from Wahoo, it wouldn't be a huge deal.

I did set the AXS bike up on the 11 speed cassette today for a quick test. I didn't even have to microadjust the RD, just found a sprocket that lined up and it's as smooth and quiet as can be. That'll work for dedicated workouts.

[zscs]

When I upgraded my old SRAM 11-speed system to an Eagle AXS last year, tested the AXS system with the old rear wheel and 11-speed X01 cassette on it and worked surprisingly fine (I only had to focus on that, do not try to shift to the - non-existing - 50t cog ).
Never tried it but came to my mind: a 12-speed AXS system should work fine even a 11-speed SRAM/Shimano cassette maybe, like in case of MTB cassettes?
Spacing between the cogs are very close as far as I remember (have to double-check it though). If this would be the case then literally you could put your 12-speed bike on a trainer with 11-speed cassette. (Just be aware that you don't shift the 12th gear.) Any of you tried this?

[JMeinholdt]

When I upgraded my old SRAM 11-speed system to an Eagle AXS last year, tested the AXS system with the old rear wheel and 11-speed X01 cassette on it and worked surprisingly fine (I only had to focus on that, do not try to shift to the - non-existing - 50t cog ).
Never tried it but came to my mind: a 12-speed AXS system should work fine even a 11-speed SRAM/Shimano cassette maybe, like in case of MTB cassettes?
Spacing between the cogs are very close as far as I remember (have to double-check it though). If this would be the case then literally you could put your 12-speed bike on a trainer with 11-speed cassette. (Just be aware that you don't shift the 12th gear.) Any of you tried this?

I tested it out on my 11-28 11 speed shimano cassette. I've done a couple ERG mode rides in one gear no problem. I've flicked through a couple gears on either side and it's still spot on. Haven't gone to the ends of the cassette yet. Maybe I'll try that today. The flat top chain is narrower so it appears to have a bit of extra space on either side which makes it less likely to rub. I'll update with results.

Obviously, this isn't ideal, but it may be good enough to not have to spring for a $70 free hub, $185 cassette, and the hassle of swapping.

[zscs]

Sounds good, thanks!

[JMeinholdt]

Sounds good, thanks!

On my latest ride I ran it through all of the gears in both the big ring and little ring. There were only a couple combinations where there was noticeable rub. Otherwise it shifted through great.

That was just a quick couple minute test running through them. I'll try to do a longer ride in the next few days and spend more time shifting through the gears to see if it's really a viable combination.

[zscs]

Really great, thanks a lot! This information is really helpful. I also hoped for that, with the narrower 12-speed chains there must be some extra tolerance between cogs, even if cassette spacing is not 100% identical.
I plan to test mine with a 12-speed MTB on the 11-speed 11-28 road cassette on the trainer. Just need to wait until I get the Boost adapter I've just ordered (currently I have only an old Elite Kura trainer to be honest - waiting for that the Kickr will be available for purchase again in German webshops).

[JMeinholdt]

Totally forgot about posting a link to the video I made about running AXS on the 11 speed trainer. It's not too bad and I've been using it in ERG mode this way most of the winter.

https://youtu.be/DBQFZ8f4Hgo

I am still curious about getting an HG compatible 12 speed cassette to try. Maybe I'll do that in a few weeks.