There are way more crappy hubs out there than good hubs. This is especially true for rear hubs, which are more complicated and therefore easier to muck up from an engineering perspective. All good hubs share the following features:
Sealed cartridge bearings of good quality. Enduro stainless bearings are a fine baseline here. Good sealed bearings are low maintenance, they’re cheap to replace when they’re shot, and they keep crud out.
Wait. What is a sealed cartridge bearing? Oh man, this is gunna be the longest hub write up ever. Sealed cartridge bearings, in a nut shell, are made of two bearing races with grooves cut in them for bearings to ride in. The two bearing races form an inner and outer shell of the bearing. Covering the gap between these two races is a seal, which is generally made of a soft plastic. This seal, contrary to much popular belief, can be pried off, and the bearings can be serviced. These seals keep crap from getting in the bearings, but they won’t help you if you blow a bunch of pressurized water at them, or just ride a ton in the rain.
We prefer stainless steel bearings to ceramic, because they’re less expensive, and less hard on the bearing races. They also have a higher static load rating (IE brute force collisions like a pothole) than ceramic. Go steel!
Hubs ideally have a way to adjust bearing preload. Some hubs have non adjustable bearings. You can’t get rid of bearing slop as the bearings wear. Bad! Good hubs have adjustable bearing preload. Good hubs also have thick flanges for a strong spoke interface. They have big fat axles for stiffness. Bearings that are normal-to-big sized.
Last on the nice hub wish list: good looks, good colors, easy to find replacement parts.
Rear hubs have a whole host of additional needs. The drive mechanism needs to be robust. 3 pawls is fine (White Industries) if they are very precisely machined. 2 Pawls is lazy. (Mavic, DT’s cheapest hubs). Pawl redundancy is good. Hey. What the heck even is a pawl? It’s a tiny spring loaded piece of hard steel that sorta folds outta the way when the hub is coasting, and springs into action to lock against ratchet teeth when you hit the pedals. More pawls means a more robust engagement. Pawls have downsides: they’re kinda noisy, don’t like dirt or mud, and they require really exacting manufacturing tolerances to nail. I’ve seen hubs where one or more pawls engage slowly or too quickly, because of bad tolerances. As a result, all the drive force can be shared by one pawl, while the others flail around like James at a high school reunion.
Ok, so if pawls work, but can be a pain, what is the future?
There are a number of different options out there, but for our money, the best thing going is the Onyx sprag clutch. It’s difficult to explain, but think about a bunch of little doodads, that as soon as you hit the pedals, expand and hit the inside of the hub shell. These function kinda like pawls. As soon as they hit, you are going forward. Unlike pawls, they engage instantly, all at once. There is literally no lag. They also make no sound, so coasting is both completely drag free and silent. The sprag clutch on an onyx hub is hidden behind a row of bearings, so contamination has to get thru a high quality bearing before it can mess with the clutch.
Rear hubs ideally have at least 4 rows of bearings. More is better. More bearings = less wear per bearing. The bearings should be replaceable.
The Onyx hub is heavy. Not insanely heavy, but it’s a chunk when compared to a White Industries hub. That’s mainly because of how beefy everything is. It’s not really a symptom of the sprag clutch, which isn’t actually very big. It’s because the axle is huge. The hub shell is robust. The flanges are thick. The bearings are big. If you want the strongest, best sealed, lowest drag, fastest engagement hub out there, and don’t mind 100 extra grams, give these a look.
Other fun stuff: US made, insane color options, and you can get a small graphic custom engraved on the hub shell at no extra cost. It has to be pretty high contrast, and simple, but they can do it.
Holler at us to help spec some Onyx hubs for your next wheel build or custom bike build. We’ll walk you through all of the options!