Just got a new bike (CAAD optimo 2) and a used zwift hub one. Installed the bike on the hub and this happens when 1. I pedal extra hard 2. I switch gear virtual and the resistance gets higher.
If I start biking it will skip once or twice and if I keep a smooth and low watt rythm it will work mostly fine.
Not sure how I can post a video, but uplaoded a picture of how it looks. To me the chain looks alligned, and it doesn’t make any noise or skip when I pedal lighlty.
Here is the video: streamable .com / kzrh54 (remove spaces)
Hyperglide is the freehub format. Lots of options out there. Wolf Tooth stainless would be top quality but there are many inexpensive options. You’ll probably need some spacers as well. Where do you live?
You could also take it to a bike shop and have them sort it out.
You could do that but would be a pain to take it off every time you wanted to put it back on your wheel for outdoor riding. You can find single speed sprockets online pretty cheap, should just easily replace the one in the cog.
You should try that since you already own the cassette.
Here’s an example of an inexpensive Hyperglide single speed conversion kit. This one has 13 teeth instead of 14 on the Zwift cog but it should still be OK.
Thanks! I’ll try and buy one tomorrow maybe, or just install my cassette on it for this season. But you think this is the problem? Even though the previous owner told me he only used it 30-40 times.
Should work fine. Or If you have another HG cassette lying around (same speed) that isn’t too worn, you could try removing a ring off that and put it in the Zwift Cog.
Yeah just try your cassette. If it stops the skipping you’ll know its that. Its possible the guy before used it with a worn/stretched chain and that will wear the teeth.
It’s really hard to tell from the video. In the picture I thought your derailleur might not be perfectly lined up with the cog, but the way it jumps makes me think there is something about how the chain is fitting on the cog (possibly from wear). It’s very hard to diagnose from a video, so taking it to a bike shop might be more helpful, but since you have a cassette you could try that and see if it’s better.
I’m a bike mechanic with ~40 years in the industry. Judging by this photo - your rear derailleur is not aligned underneath the rear cog. The camera angle might be deceiving but from this perspective the derailleur is offset to the right, and the derailleur hanger is also bent.
View the top and bottom pulleys of the derailleur together. Draw a centered line between the two, and that line should be vertical. In this photo, that line is substantially tilted off vertical.
Draw another vertical line down the center of the rear cog. When your derailleur is adjusted correctly, the red line should be directly underneath the white one, and both should be vertical.
It looks like the derailleur hanger (the part of the frame circled in red) might be bent. That’s not helping alignment, like building a house on a crooked foundation. A decent bike shop will have a hanger alignment tool to precisely straighten it, and I’d recommend you do that as a first step.
@Paul_Southworth@sku77@shooj Problem solved now with my own cassette installed. Thanks so much for the help. Will try to buy an extra ring soon and install that on the zwift cog so in the spring I can more easily switch between trainer and wheel.
Good to hear. 99% of the time skipping like that under load its down to worn cassette teeth combined with a new chain. Even if the cage isn’t perfectly aligned it shouldn’t skip like that, although it may result in misshifts and premature wear. Maybe check alignment like the other guy said.
