Received my hub today and went through the setup following the manual and eventually watched the videos as well. Feel pretty confident I’ve got the setup correct but mine is grinding on my lower (smaller) gears. My bike has an 11-34 9-speed cassette. I ordered my hub with the 9-speed which I’m pretty sure is an 11-28. The hub seems to grab the next higher gear when I’m in the smaller 4-5 gears. Once I’m in the top end of the cassette I don’t hear it grabbing / grinding as much. I’m afraid to adjust my rear derailer because I don’t want to cause a problem when I put my wheel back on.
When I opened the box a small spacer fell out and I thought they might have just missed installing it so I took the cassette off the trainer but I found a spacer already installed between the cassette and trainer.
I’ve only been cycling for a few months so I’m new to understanding the cassettes and shifting. Just wondering if this is a simple fix that I might be overlooking.
I measured my rear frame clearance and felt it was 142mm with the cards in the box (2021 Giant Content AR 3 w/ Thru Hub Shaft). When I measured using a caliper I was more in the 145mm range. I’ve tried flipping the spacer to the 148mm side but I wasn’t able to get my axle to tighten so I feel it is correct with the 142mm setup.
I’ll forward this to support if I don’t get anywhere I was just hoping to get in a few rides this weekend on the new trainer.
Is the Hub internals grinding, or is it something with the chain/rear derailleur and cassette that’s grinding (ie. something electronic/motor-related, or something mechanical external of the trainer)? The Hub itself doesn’t know what gear you’re in obviously.
Is your chain length too long, seeing as it was seemingly sized for a 34 tooth cassette? Do you have the issue in the smaller rear cogs no matter if you’re in the large or small front chainring (assuming you have double chainring (though conceivably you might have a triple?)?
I don’t hear anything just spinning the Zwift Hub. Pretty confident it’s a mismatch on the cassette. To test I pulled my cassette off my wheel and put it on the hub and most of the noise cleared up. I’m going to order a second identical cassette to what is on my wheel and go with that for now.
I didn’t want to adjust the indexing for the hub only to have to redo it for my wheel every time I switch back and forth.
The spacers are for different speed cassettes to fit the hub.
you may need to index the gears due to the alignment of the cassette on the hub of the trainer compared to the hub of your wheel. Also, when you tighten the quick release skewer if you have this tighter or looser than it previously was this can slightly affect the position of the rear mech hanger so can mean you need to tweak the indexing slightly.
After trying 2 different bikes adjusting limit screws, indexing. The zwift hub excessively grinds. The grinding and vibrations make the ride unbearable. I am seeing multible threads and comments with this problem. Obviously this is a new product with problems. This problem needs to be addressed by zwift quickly. If you have the same problem please comment so zwift can see. I have already started contacting zwift.
I wonder how many folk are using a now-worn chain with their new Zwift cassette? I’d suggest that it’s worth trying a new chain, or switching cassettes from your bike in order to eliminate that issue (as well as learning how to adjust the indexing quickly).