I read in the Onyx thread that rear hub NDS bearings were getting a bit gritty for a few people with minimal use, suggesting that it has a vulnerability to contamination. Didn't seem to be using a known brand of bearings. Looked it up and can replace it (6902). An NTN bearing in that size is like $20.
I have two sets of Onyx Classic. Just picked up one second hand. The one I had before is still flawless, while the second-hand one I got from someone in AZ is a bit gritty and has slightly more noticeable drag in the freewheel. The flawless one feels like it can replicate VitalMTB's test, where it freewheeled for 2 minutes, while I doubt the second-hand one can. Edit: tested it and it does 15 revolutions when giving it a twist, while gripping the rear wheel around its freehub, vs 11 for a DT 190 with 18t ratchet). Looked up how to service it, and looks doable. I picked up a slide hammer collet bearing (blind hole bearing) remover toolkit from Harbor Freight for under $50 that I figure would be useful for the task. Already have press tools from other press jobs needed on the bike.
I've tried i9, CK, and most levels of DT. The silence is truly luxurious. I don't understand the need for noisy hubs, unless you're some former BMX skatepark rat, who drooled at all the noisy hubs on the high end bikes. That doesn't work as well on the dirt as it does in those areas with kids on scooters whizzing around, maybe only alerting people 2-3 bike lengths away. Rather alert people 15 bike lengths away, with a loud enough bell.
I'm sold on Onyx. I hate loud noise, unless it's tuned to sound pleasing. One exception: I recall a hub sounding like a cricket/cicada, that I actually thought was nice.
Only other hub on my radar is the Project321 one. CK was kind of pricey to convert, but had some impressive sculpted detail and quality put into it; they just were a bit draggy and noisy. I had old i9s that were slightly draggy, and were system wheels with alum spokes. The alum spokes gave me more feedback with the ground, making me more in tune with where the wheels were and what they were doing, elevating my ride handling, but since I'm not so into high performance anymore, that finer grain feedback is just noise to me now. DT just worked flawlessly. Reliability was expected. I had an issue with old 350s yard sale-ing their guts whenever I pulled the wheel out of the dropout, due to the weight of the cassette pulling the freehub off if it was leaned in a direction that gravity could work on it. Didn't have that issue with 240s, since I guess the end cap had a more pronounced detent holding it. I learned that Centerlock versions of hubs also come with smaller bearings, which turned me off.
