Skipping Gears on a Hub One

Just got a Zwift Hub One on 11/12/2023. Rode it about 6 times. First four times it was AWESOME!!! Last two rides one minute is sounds as if the chain wants to sip a gear. (However, Hub one only has on cog). The very next minute the trainer has the feel on a chain skipping three times. Everything works fie for about 10 minutes then the cycle starts all over again.
I am new to the indoor cycling world. Any ides to what is going on? Tried multiple attempts to contact Zwift, negative results. Not sure why they do not have a customer service department?
Any help? I do not want to ruin this new trainer.

Two things.

How old is your chain? If it’s worn the new cog of the hub could cause it to jump.

And are you in a gear where your rear mech is bang in line with the Hubs Cog?

Just thought, are you using a different chainring on the front that you were? Ie. Mostly ride in the big ring but now are using the small ring?

Chain only has 150 miles on it. I have a granny gear on the front but I use the middle chainring while using the Hub One.

Check the wear on that chaining then.

Look at the comparison here.


Unless ride #4 was extremely long, I’m thinking it probably doesn’t sound like a worn drivetrain issue if between rides 4 and 5 it went from nonexistent issue to obvious issue.

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Unless there’s been a change of ring use I’m with you on that one to an extent.
That said in my experience I’ve known a worn chainring to expose itself mid ride on more than one occasion. Usually when you are putting down big pressure, ie pushing a high gear at low cadence.

They just seem to fall off a cliff all of a sudden.

I suppose, though it wasn’t mentioned where the skipping feeling (or is it just a sound?) is coming from. I don’t think a worn front chainring can cause skipping in the rear.

I am more skeptical of the the actual cogs that are used in the HubOne, with their quite unconventional tall tooth shape, and I think I have already read reports of some of these teeth already shearing off. I’d be curious to know who was sourced for the actual manufacturing of these cogs.

I’ve been waiting to see any reports of owners doing their own swap-ins of an actual Shimano cog onto the HubOne to see what, if any, difference there may be in performance.

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The tooth profile is normal for single speed cogs. Hard to guess what might be the issue. If it worked for a while and then suddenly started making a noise without any changes, and with the derailleur in proper alignment with the cog, I would start wondering if the noise is coming from the trainer.

It would be sensible to take the trainer and bike to a bike shop for evaluation.

It is possible to contact Zwift support if you play the chat bot game for long enough.

Possible problem with the pawls in the freehub.

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I think this might be quite likely.

does the skipping happen after freewheeling for a bit? could be the freehub body isn’t engaging properly.

if you’re abl to remove the freehub and check these bits spring back up when pressed down:

sometimes too much grease can mean they don’t spring back up as they should.

Well, maybe if they used an actual single speed cog, it could be an issue.
Single-speed chains have an inner width of 1/8″ (3.175 mm).
Multi-speed chains, from 5 to 8 speeds have an inner width of 3/32″ (2.38 mm).
Multi-speed chains from 9 to 12 speeds have an inner width of 11/128″ (2.18 mm).

From an interesting article at:
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The thing that has bugged me about the One, is that somehow they’ve created a machine with a cog that somehow is supposed to be compatible with anyone’s chain.

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I’m talking about the tooth profile, not the thickness. Single speed cog teeth are taller. There are plenty of single speed cogs designed for 3/32" chains.

Though the Surly model is only compatible with up to 9 speed. interesting.

The WolfTooth site indicates taller teeth are for the purpose of more reliable chain retention. Also that cog is best for 9-11 speed chains but can work with 12 speed. There seems to be no reason to have chosen this tooth profile for the hub, where most(?) riders are putting a multi-speed bike on the trainer that has a RD that provides chain tension, and hopefully not hitting any potholes while riding in Zwift.

Anyway, that would be first try in fixing a noisy rear. A single cog, built for my speed drivetrain. Eg. for an 11 speed shimano drivetrain:
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Sure try whatever you want. I don’t have a Hub One so I can’t do the experiment.

I have ridden Miche cassettes though and I sheared off a handful of teeth on two of them. I concluded they are rubbish.