Astral Serpentine Carbon Rim
The Astral Serpentine is the carbon all-road rim from Astral, the rim brand of Rolf Prima in Eugene, Oregon: a modern wide bed for 28 to 42mm tires, a moderate depth that balances aero and comfort, Astral's Tubeless Easy bead and a carbon layup tuned for the road-to-gravel riding most drop-bar bikes do now. It is the carbon rim we build for endurance road, all-road and light-gravel bikes that want one wheelset for everything.
This page covers the Astral Serpentine Carbon Rim in 29in. The Serpentine is not sold bare. You choose the hub and the rest of the build in the configurator, and it ships from our shop in Georgia laced, tensioned and trued by hand.
Design and construction
The Serpentine is a carbon disc rim with a wide inner bed that gives a 30 to 35mm tire a round, fast profile, a section deep enough for a real aero benefit on the road and shallow enough to stay comfortable on dirt, and Astral's Tubeless Easy bead shelf that seats a tire with a floor pump. The spoke holes are angled toward the hub flanges so the nipples sit straight, and the layup adds material at the bead and spoke bed. External nipples, standard J-bend spokes, disc only. The Serpentine X is the wider version for bigger tires.
How it rides
A Serpentine wheelset is fast on the road, calm in a crosswind and comfortable on gravel with a 35mm tire. It is the rim for the rider who does a road race on Saturday and a gravel ride on Sunday on the same bike. For wider tires the Serpentine X is the better bed; for pure gravel the Outback.
Specifications
| Wheel size | 29in |
|---|---|
| ERD | 592.5 (29in) |
| Inner width | 30 mm |
| Depth | 25 mm |
| Drillings | 24h, 28h, 32h |
| Weight | 400g (700c/29in) |
| Material | Carbon Fiber |
| Tire type | Clincher Tubeless Compatible |
| Brake | Disc |
| Profile | Triangle |
| Nipples | External |
| Finishes | black |
This listing
This is the 29in listing of the Serpentine, 24h, 28h, 32h, about 400g, 30mm inside, 25mm deep, disc. Pick the size that matches your frame; the profile and construction are the same across the range.
This is the disc-brake Serpentine: plain sidewalls, no brake track to wear, a touch lighter. It fits any disc-brake bike and it is the version most of our customers now build; the rim-brake version is a separate listing.
Sizes, fit and compatibility
The Astral Serpentine Carbon Rim comes in 29in and 24h, 28h, 32h drilling. It is a disc-brake rim. We build the Serpentine on DT Swiss 350, 240 and 180, White Industries CLD, Industry Nine 1/1 and SOLiX, Chris King R45 and Hope RS4 hubs, usually with Sapim CX-Ray or CX-Sprint spokes or DT Aerolite, and brass or alloy nipples.
Tire range on the Serpentine is 28 to 42mm. Pick road, all-road or gravel as your bike type in the configurator and it recommends a spoke count and lacing pattern.
Put it in a custom wheel
Build a custom wheel around the Astral Serpentine Carbon Rim — the link drops you into our Custom Wheel Program with this rim pinned, ready for you to choose the rest. It is set up for gravel and road disc, mountain bike, MTB single-speed and fat bike builds.
Spoke head is decided by the hub, not the rim: this rim builds equally well with J-bend or straight-pull spokes, and the configurator only offers the spokes that match the hub you pick.
What Astral says about testing
Astral Cycling is the rim brand of Rolf Prima; both operate from one facility in Eugene, Oregon, where Rolf Prima states alloy rim production has been in-house since 2014. Astral joins alloy rims with a press-fit sleeve about 2.5 inches long weighing 4-5 g that doubles the wall thickness at the joint, avoiding the heat-affected zone of welding. All wheels are hand-built in Eugene. Rolf Prima states it does not farm out testing and has logged "over 10,000 hours of lab testing to above industry standards."
Warranty: Astral states alloy rims are covered two years and carbon rims five years for the original owner, excluding impact damage; Rolf Prima wheels (2016 and newer) carry five years, bearings two years, plus lifetime discounted crash replacement for registered wheels.
Astral's videos
From Astral
Certifications
- Made in USA (alloy rims and wheels) — Astral and Rolf Prima state alloy rims are rolled and all wheels hand-built in their Eugene, Oregon facility; rim production in-house since 2014 (source)
- ISO 4210 base + in-house standard — Fatigue drum at 47 mph vs ISO 15 mph, life requirement 66% above ISO; UCI 40 J impact plus higher in-house level; ISO 4210 dry/wet brake tests (source)
- UCI note — Rolf Prima FAQ: Aspin and Elan family are 'Standard' wheels not requiring UCI approval; no approved-model list verified (source)
- Rolf Prima Certainty — In-house engineering and testing lab, eleven patents, over 10,000 hours of lab testing, 5-year warranty, lifetime crash replacement (source)
Sources on Astral's site:
- Testing – Astral Cycling
- FAQ's – Astral Cycling
- Astral Rim Warranty – Astral Cycling
- Technology – Astral Cycling
- Rim Joining: The Process and the Mystery – Astral Cycling
Everything in this section is published by Astral. ProWheelBuilder is the wheel builder, not the tester, and the rim reaches us as the maker ships it.
Building it at ProWheelBuilder
Astral makes the Serpentine; ProWheelBuilder is an independent wheel builder in Georgia, not the manufacturer. Every Serpentine wheel we build gets spokes cut from the rim's measured ERD, is tensioned in stages with a gauge, stress-relieved and trued before it ships. Tubeless tape and a valve are fitted on request.
In the configurator you will only see parts that fit this drilling; combinations that are not made are struck through, and the price updates as you pick.
Warranty
Manufacturer's warranty. Rolf Prima gives a one-year limited warranty on its wheels under normal use. Astral is Rolf Prima's rim brand; ask us and we will confirm the current terms for the exact rim before you buy.
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.
Serpentine Carbon Rim questions
What tire width suits this rim?
At 30mm inside this is a trail width, sized around 2.1 to 2.4in tires. That is wide enough to stop a modern trail casing rolling under you in a corner without pushing the tread so flat that it wears down the middle.
Serpentine or Serpentine X?
Serpentine for 28 to 38mm tires and road-first riding; Serpentine X for 35 to 45mm tires and gravel-first riding, with its wider bed.
Is the Serpentine tubeless?
Yes. Astral's Tubeless Easy bead seats a tubeless tire with a floor pump; we tape and fit a valve on request.
What tires fit the Serpentine?
28 to 42mm. A 32mm road tire or a 38mm gravel tire is the usual pairing.
Who is Astral?
The rim brand of Rolf Prima, the wheel company in Eugene, Oregon.
Is it tubeless-ready?
Yes. Astral lists the Serpentine Carbon Rim as clincher tubeless compatible; we tape and fit a valve when you choose the tubeless option.
Which spoke count should I choose?
It depends on your weight, terrain and the hub, not the rim alone. The configurator recommends a count from your bike type and rider weight, within the drillings this rim is made in.
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.
