Onyx Vesper Road Rear Hub
The Onyx Vesper road hub brings the sprag clutch to road and gravel bikes: instant engagement with no teeth to skip between, total silence when coasting, and Onyx's lightest hubshell, machined and anodized in Minnesota, in 12mm thru-axle road and gravel spacing with centerlock or 6-bolt rotor mounts. A silent hub on a road bike is a strange luxury the first time and hard to give up afterwards. This page covers the Onyx Vesper Road Rear Hub.
The Vesper road hub comes from us only as a finished wheel: pick the rim, spokes and nipples, and we lace, tension and true it by hand in Georgia before it ships.
Design and construction
The Vesper is the lightest shell Onyx makes, and it carries the same sprag clutch as the heavier hubs rather than a reduced version of it: no teeth, no engagement points, and nothing to click when you stop pedalling. It is machined and anodized in Minnesota for 12mm thru-axle road and gravel spacing with centerlock or 6-bolt rotor mounts.
Silence is the part riders notice first on a road wheel. A freehub that ticks is the loudest thing on a quiet lane, and the Vesper simply does not make the noise.
How it rides
A Vesper road wheel coasts in silence and engages the instant you push, which on a cyclocross start or a gravel climb is a real advantage and on a group ride is simply pleasant. The bearings roll freely, the labyrinth seal keeps grit out, and the hub weighs no more than the boutique road hubs it competes with.
Specifications
| Position | Rear |
|---|---|
| Axle options | QR 5x130mm Rear |
| Driver bodies | Shimano HG 8,9,10,11 & Road 12spd (Aluminum), Campagnolo 9,10,11 & 12spd, Campagnolo N3W 10,11,12 & 13spd, Shimano Micro Spline 12spd (+$75), SRAM XDR 10,11 & Road & MTB 12spd |
| Drillings | 24h, 28h, 32h |
| Spoke head | J-bend |
| Brake | rim-brake |
| Left flange diameter | 38 mm |
| Right flange diameter | 50 mm |
| Left center-to-flange | 34.6 mm |
| Right center-to-flange | 17 mm |
| Spoke hole diameter | 2.6 mm |
| Weight | 325g |
| Material | Aluminum |
| Finishes | baby blue pc, black ano, black aura pc, black matte ano, blue ano, blue candy pc, clear ano, gold ano, green ano, green anti freeze pc, green florescent pc, green kawasaki pc, orange ano, orange florescent pc, pink ano, pink florescent pc, purple ano, purple candy pc, red ano, red candy pc, turquoise ano, white pc, yellow cardinal pc, yellow florescent pc |
About this listing
What sets this listing apart from the other Vesper versions: rim-brake rotor mount, QR 5x130mm, 24h, 28h, 32h drilling, about 325g, in baby blue pc, black ano, black aura pc, black matte ano, blu. Pick the one that matches your frame and rotor and the rest of the hub is identical.
This is the rim-brake Vesper, with no rotor mount at all: a lighter, simpler shell for road, track and classic frames that stop on the rim. It builds into the lightest wheel the model can make and it is the version to choose for a rim-brake bike; the disc versions of the same hub have their own listings.
Sizes, fit and compatibility
The Onyx Vesper Road Rear Hub comes in the drillings listed on this page with the axle, rotor and driver options shown in the configurator, in 12mm thru-axle road and gravel spacing. J-bend spokes in any gauge; we build most Vesper road wheels with Sapim CX-Ray, Laser or D-Light spokes or DT Aerolite and brass or alloy nipples.
It pairs naturally with ENVE SES and G-Series, Reserve, HED, Nox, Boyd and DT Swiss road and gravel rims that match its drilling. Pick your bike type and weight in the configurator and it recommends a spoke count and lacing pattern.
Build it with us
We build this hub to order. Open the Custom Wheel Program with the Onyx Vesper Road Rear Hub already selected and pick the parts around it; it is offered for road rim brake and touring builds, and the configurator will not let you assemble a combination we would not build.
Testing, standards and warranty at Onyx
Onyx Racing Products hubs are made in the USA by a division of Christianson Systems in Minnesota; in a 2020 interview the company described itself as "Minnesota made and owned". Hub shells are machined from 7075 aluminum (retailer listings cite 7075-T651 with heat-treated stainless steel and titanium hardware), and Onyx's European distributor states Onyx freehub units "are made out of high-grade 7075 aerospace-grade aluminum in the USA". Bearings are hybrid ceramic on the Classic line and an upgrade option on Vesper; the distributor states "Since early 2025 all Onyx hubs have been assembled with high-quality Japanese EZO bearings." Onyx specifies a grease service temperature range of -58°F (-50°C) to 248°F (120°C). It publishes no bearing-cycle, salt-spray, ISO 4210 or load-test figures. Onyx's specifications state radial lacing is not permitted on any Onyx hub and set a maximum spoke tension of 120 KgF.
the patented sprag clutch is a one-way clutch of cams between two races, giving instant engagement, instant disengagement when coasting and silent operation; BMX hubs use a single-row sprag assembly, mountain, road and gravel hubs a double-row assembly. Onyx publishes no numerical torque capacity; its distributor states Classic hubs "are e-bike approved for bikes that have a mid-drive unit with a peak power output of up to 1500W."
Onyx's videos
Inside the Onyx shop
Certifications
- Made in USA (Minnesota) — Onyx states it is "Minnesota made and owned"; retailer and distributor listings state "Made in the USA" (source)
- 5-year limited hub warranty — Hub 5 years to original owner; sprag clutch 1 year against manufacturing defects; wheel builds 1 year (source)
- E-bike approval (Classic hubs) — Distributor states Classic hubs are e-bike approved for mid-drive units with peak power output up to 1500W (source)
Sources on Onyx's site:
- Onyx Racing Products - Tech (site returned 403 at time of research)
- Onyx Racing Products - Limited Warranty (U.S. Only)
- Onyx Racing Products Wheels - Warranty
- November Bicycles: In their own words - Onyx Racing Products (April 17, 2020)
- Onyx Hubs Europe - Technology
The figures, certificates and media above are Onyx's own. ProWheelBuilder does not run these tests; our part is the wheel we build on the hub.
Building it at ProWheelBuilder
Onyx makes the Vesper; ProWheelBuilder is an independent custom wheel builder in Georgia and not the manufacturer. We measure the rim before we cut a spoke, bring the wheel up in three or four rounds with a gauge, stress-relieve it between rounds and true it last, then tape it and fit a valve if you want it tubeless.
Only compatible hubs and spokes appear in the configurator, impossible combinations are struck through rather than hidden, and the price is live.
Warranty
Onyx's warranty. Onyx Racing Products covers its hubs under a five-year limited warranty against defects in materials and workmanship.
ProWheelBuilder. Built into a wheel by us, this part is covered by our own one-year wheel warranty on top of the maker's. For a year we replace broken spokes whatever caused them, and we cover the labor on the wheel - truing, re-tensioning, a rebuild if it needs one. If a rim or hub fails and its maker covers it, we run that claim for you; if the maker says no, you get an eligible replacement rim or hub at 25% off retail. You pay the shipping each way. Wheels built from parts you send us are excluded.
Full terms are on our Policies & Warranty page.
Vesper Road Rear Hub questions
Can I use this hub with disc brakes?
No - this is the rim-brake version and it has no rotor mount at all, which is exactly why it is lighter and simpler. It is the one for a rim-brake road, track or classic frame. A disc frame needs one of the disc versions of this hub, which are listed separately.
Which spokes and nipples suit the Vesper?
For most riders a double-butted spoke such as Sapim Race or DT Competition with brass nipples; lighter riders can go to Sapim Laser or CX-Ray. The configurator recommends a gauge and count for the Vesper from your bike type and weight.
How does a sprag clutch work?
A ring of tilting hardened-steel cams wedges against the race the instant you pedal and releases the instant you coast. There are no teeth, so engagement is instant and coasting is silent.
Vesper or Onyx Classic?
Vesper for cross-country, trail and enduro where weight matters; Classic for downhill, e-bikes and the heaviest duty, with more sprag rows.
Which drivers fit the Vesper?
Shimano HG, SRAM XD and Shimano Micro Spline, swappable on the common axle and selectable in the configurator.
Is the Vesper e-bike rated?
No. Onyx rates the Vesper for pedal bikes; the Onyx Classic is the e-bike and downhill hub.
Which axle spacing does it fit?
QR 5x130mm Rear. Measure between the inside faces of your dropouts if you are unsure, or text us.
Not sure? Text or leave a voicemail on 470-253-0929 or email info@prowheelbuilder.com — you will be talking to the people who build the wheels.
