Please select Freehub (Hyperglide, Microspline or XD) and/or End Caps from HERE after your selected hub has been added to the cart.
Compatible End Caps – 15×110, 15×110 Torque, 20×110 Boost
Industry Nine Classic hubs are the heart of your wheelset, everything revolves around them, literally. Every Classic mountain hub is made start to finish in our Asheville, NC machine shop. From turning and milling bar stock 7075-T6 aluminum for shells, axles and encaps, wire EDM cutting A2 tool steel for pawls and driverings, to our own in-house anodization lab, every step of design, engineering, manufacturing and assembly is done on premises to our exacting standards.
Hydra Classic mountain hubs are loaded with features every rider will appreciate such as revolutionary 0.52° engagement, generously low weights and an intuitive layout that can be serviced without any proprietary tools. Our range boasts a universe of standard options in terms of axle fit, spoke hole drillings, disc rotor mounting, freehub bodies, and colors.
Will this fit my fork?
This is the Boost version, so it suits any fork with 110mm hub spacing. It runs 15×110 Boost, 15×110 Torque Cap, or 20×110 Boost, depending on your fork.
Most modern forks are plain 15×110. RockShox forks with the wider 31mm inset crown take Torque Caps, which sit deeper and add a little front-end stiffness. Older or heavy-duty forks use a 20mm axle. If your fork is 100mm spacing rather than 110mm, you want the non-Boost version of this hub instead – tell us the fork model and we’ll confirm which you need.
Should I get 6-bolt or Centrelock?
This is the 6-bolt version. The simplest rule is to match whatever your rotors already are – swapping rotor standard means buying new rotors, which is rarely worth it.
If you’re starting from scratch, 6-bolt is the safer pick. Rotor choice is wider, replacements are easier to find, and all you need is a T25 key rather than a cassette lockring tool. Centrelock is quicker to change and marginally lighter, which matters more to racers than to most riders. We stock this hub in both, so ask if you’d rather have the Centrelock.
Should I choose 28 or 32 hole?
Let the rim decide, and don’t assume more spokes is automatically better. Plenty of enduro wheelsets are specced 28 hole on purpose – a slightly more compliant wheel tracks better and finds more grip on rough ground than a stiffer one does.
Follow the rim manufacturer’s guidance for the rim you’re building onto; they’ve tested it. If you’re replacing a hub in an existing wheel, match what your rim already has. Tell us the rim and we’ll confirm before you order.
Can I build this with normal spokes?
Yes. This is the Classic hub, which takes standard J-bend spokes – so any decent spoke will do and you’re not tied to Industry Nine’s proprietary alloy ones. That’s the difference between these and I9’s System wheels, which is where most of the confusion comes from.
We build wheels in-house, so if you’d like it laced to a rim, tell us the rim and spoke count and we’ll quote the build with it.
