Alright so forgive me for my lack of knowledge - I have a Critical Cycles Harper fixed-gear bike, and hoping to invest in a used KICKR core or some other cheap trainer to set it up with. I understand I need some sort of cassette, new chain, freehub, but these are all brand new concepts and terms for me. Ideally, I would love if the setup could have automatic resistance, but I just want to know what my options are. I’m struggling to understand all the technical details and am getting overwhelmed. Thank you in advance for your patience!
it should be fairly simple.
little old but should be similar although there is newer version of clik now.
With this,
The problem with using fixed gear bikes on a direct drive trainer is that most of them have 120mm axle spacing, but the minimum rear axle width for a direct drive trainer is 130mm. You should measure the axle spacing of your bike before getting a trainer, to understand your options. There is an adapter kit available for bikes with 120mm spacing, but it’s not cheap and will require replacing the chain as well because it will need to be longer. Turbo Trainer Single-Speed Adapter – Velobike
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Hi @J_Bellis welcome to Zwift forums.
Shuji at Zwift HQ here. I’m not familiar with Critical Cycles, and their website does not provide two key pieces of information that’s crucial to know to guide you toward the right trainer. You can determine this by removing your rear wheel and measuring the frame with a tape measure (hopefully metric).
- Rear axle width (or the inside<>inside width of your frame measured with the rear wheel removed.
- The frame’s rear dropout style: is it a more-or-less horizontal slot, or a more-or-less vertical slot? Snap a photo of the rear wheel from the bike’s drivetrain (right side) to show us.
120 mm frame width means you can’t use a wheel-off type trainer without also modifying it with a n adpater like the Velobike one that Paul lists. This type of modification makes sense if you’re a dedicated track cyclist and want to train on the same bike you race with.
Instead, you may want to consider a smart trainer that you use with the rear wheel still on the bike. More on that below.
130 mm frame width means you can use a wheel-off aka “direct drive” smart trainer AS LONG AS your frame has horizontal dropouts. The horizontal slot will allow you to take up the slack in your chain that would otherwise be taken up with a rear derailleur (which your bike lacks).
10 years ago when Zwift was still in its infancy, direct-drive trainers were very pricy and many Zwiters got started with wheel-on trainers. These days, entry-level direct drive trainers start at a price point low enough that the demand for wheel-on trainers have plummeted.
A wheel-on trainer still makes practical sense in cases like yours where the frame may not be physically compatible with a direct-drive trainer. Wahoo no longer makes the KICKR Snap, but they’re stil in the marketplace as NOS. You might look into that option or the KICKR Rollr, which is still in production. The thing to know about wheel-on trainers is that they’re not as accurate in measuring your power, and typically will inflate your power numbers a bit higher. In practical terms, your avatar might move faster in game, but unless you’re in a race where accurate power matters - it shouldn’t impact anyone else in a negative way.
Before considering a Kickr SNAP, do read the compatibility page. It advises people to avoid nutted axles and anything under 130mm as well. It may be possible to adapt a fixie to work on it, but it’s not recommended by Wahoo.
https://support.wahoofitness.com/hc/en-us/articles/8607292664466-Bicycle-Frame-Compatibility-SNAP
Personally I would avoid the Wahoo Kickr Rollr because it’s not a smart trainer unless you have a power meter on your bike. It has some other limitations but that’s the biggest one. It’s a weird trainer, not inexpensive, and if you add the cost of a power meter it probably costs more than a Zwift Ride bundle, which would be better in every way.