Rolf Prima Ares4 AR Wheelset
The Rolf Prima Ares4 AR is the all-road member of the Ares family, which has been Rolf's carbon race line for years. Where the road Ares4 uses a 42mm rim with a 20mm inner width, the Ares4 AR moves to a 40mm deep carbon rim with a 25mm inner width. That gives a wheel that Rolf describes as fast enough for competitive road riding and tough enough for gravel roads less traveled.
It suits the rider who races criteriums or fast group rides on 28s and 30s but also lines up for gravel events on 40s, and does not want to own two wheelsets. It is disc only, 700c, and built on Rolf's US-made XST 4.4 hubs with the T2 high-engagement drive.
Paired-spoke lacing is the reason a 40mm carbon rim can be laced with only 20 spokes per wheel and still be stiff enough for sprinting and durable enough for washboard. Pairing the spokes at the rim neutralizes the opposing left and right pull, so Rolf can run higher, more even tension on fewer spokes. Fewer spokes on a deep rim also means less drag, which is where the Ares4 AR gets its aero credentials.
Design and construction
The rim is a full carbon, tubeless-compatible clincher, 40mm deep, 25mm inner width, 31mm at its widest point. Rolf's tubeless-easy design ships taped with valves so a tubeless tire can be seated with a floor pump.
The hubset is XST 4.4 Centerlock: designed and machined in the USA, assembled in Eugene, with Enduro steel cartridge bearings and a CNC-machined 6Al-4V titanium freehub body. The T2 drive uses a 48-tooth ring and three independently sprung steel pawls for quick engagement.
Spoke count is 20 front and 20 rear, bladed Sapim CX-Ray, paired at the rim. Brake interface is Centerlock disc. Front axle options are 15mm or 12mm thru-axle or 9mm QR; rear options are 142mm thru-axle or 135mm QR. Freehub bodies offered on the Ares4 AR are Shimano HG 10/11, SRAM XDR, Campagnolo and Campagnolo N3W.
How it rides
On the road the Ares4 AR rides like a race wheel. Forty millimeters is deep enough to hold speed on rolling terrain and in a paceline, and the Delta profile keeps it manageable in a crosswind. Acceleration is sharp because the set is light for its depth at 1515 grams, and the T2 drive engages quickly when you jump.
On gravel the wide bed and the 25mm inner width let a 38mm or 40mm tire take a proper round shape at lower pressure, and the carbon rim damps chatter better than a shallow alloy rim. It is a firm, precise wheel rather than a plush one. For loaded touring or rocky singletrack we would point you to the 24-spoke Hyalite Carbon instead; the Ares4 AR is the wheel for going fast on mixed surfaces. Bike Rumor's line about the road Ares4, that it does it all at a height and weight appropriate for any riding, applies just as well to this wider version.
Specifications
| Wheel type | Adventure / Gravel |
|---|---|
| Rim | Carbon clincher |
| Rim depth | 40mm |
| Rim width | 31mm, 25mm internal |
| Brake | Disc Brake |
| Spoke count (F/R) | 20/20 |
| Spokes | Sapim CX-Ray, bladed |
| Hubset | XST 4.4 Centerlock T2 High Engagement Enduro Steel Bearings |
| Front axle | 15mm, 12mm, 9mm |
| Rear axle | 142mm, 135mm |
| Freehub | Shimano HG 10/11, SRAM XDR 11/12, Campagnolo 11/12, N3W |
| Tire size | Please refer to chart in product images |
| Weight | 1515g [695g/815g] |
| Includes | Taped for |
About this listing
What you are buying here is the Ares4 AR Wheelset. The choices on this page are front axle: 15mm Thru Axle Front, 12mm Thru Axle Front, 9mm QR Front; rear axle: 142mm Thru Axle Rear, 135mm QR Rear; driver type: Shimano HG 10/11, SRAM XDR, Campagnolo, Campagnolo N3W. This listing is the complete wheelset - front and rear together, not a single wheel.
Fit and compatibility
The Ares4 AR is 700c, disc only, with Centerlock rotor mounts. Front end caps cover 12x100, 15x100 and 9mm QR; rear end caps cover 142x12 and 135mm QR. Boost spacing is not listed for this model, so a Boost gravel frame should look at the Hyalite or Vigor AR lines instead.
Freehub bodies are Shimano HG 10/11, SRAM XDR, Campagnolo and N3W. Rolf directs you to its tire chart for the 25mm inner width; in practice that means 28mm road tires up to roughly 50mm gravel tires, and we think 32mm to 42mm is where the Ares4 AR is happiest. The wheels arrive taped with valves, so all you add is sealant and tires.
Testing, standards and warranty at Rolf Prima
Rolf Prima builds every complete wheelset by hand at its facility in Eugene, Oregon. The company states that all orders are built by hand there by its own builders, and describes its process as building each wheel three times with two stress cycles in the build to seat and stretch all components. Rolf Prima says hand building lets it hit uniform spoke tensions that machine building cannot match, and that its design allows higher and more targeted spoke tension than a traditionally laced wheel, which it credits with increasing stiffness and improving spoke durability by decreasing the load cycle on each spoke.
The defining feature of a Rolf Prima wheel is Paired Spoke Technology, introduced in 1997. Bringing the spokes to the rim in pairs neutralizes the left and right outward pulling forces, which Rolf Prima says allows it to build true wheels on lighter rims with fewer spokes. Fewer spokes and lighter rims are the basis of the brand's aerodynamic and weight claims. The wheel systems combine paired spokes with the Delta rim profile, internal nipples, and patented details including the Jacketed Nipple, Self-Aligning Nipple, Differential Flange Diameter and Dish Reducing Design. Rolf Prima cites eleven patents behind its technology.
Rolf Prima runs an in-house engineering and testing lab and states it uses the ISO 4210 standard as a base starting point but considers it not tough enough, so it applies its own in-house standards. Published test capabilities include an in-house drum fatigue tester it calls the Thrasher, which compresses years of riding into days; an impact test using a weight calibrated steel anvil that exceeds the UCI 40 joule requirement, striking at spokes, between spokes and at the valve hole; lateral and radial stiffness measurement of rims alone and complete wheels; brake energy, distance and temperature testing developed for carbon clinchers; wind tunnel evaluation; and field testing by sponsored athletes. The Certainty page cites over 10,000 hours of lab testing to above industry standards.
On racing eligibility, Rolf Prima explains that UCI approval only matters for mass start UCI road races, UCI cyclocross and draft legal ITU triathlon. Its standard wheels (Aspin and the Elan family) do not require approval, while most of its deeper or lower spoke count models are non standard and are listed on the UCI approval registry. Rolf Prima does not publish a fixed rider weight limit; it says every wheel has limits that involve riding style and road conditions as well as weight, and directs heavier or more aggressive riders toward stiffer models such as Vigor, Echelon or Ares6. All road wheels can be set up tubeless with the brand's tubeless kit, and adventure, cyclocross and mountain models ship tubeless ready with tape and valves installed.
Rolf Prima backs its wheels with the Certainty program: a five year warranty against defects in materials and workmanship for the original owner, lifetime crash replacement at a discount for registered wheels, a 30 day trade out or return window in the USA, replacement parts availability for any Rolf Prima wheel regardless of age, and stated service response times of same day to 24 hours on calls and email with service work resolved within three days of receipt.
Rolf Prima's videos
From Rolf Prima
Warranty and certifications
- Limited warranty — Five years from original retail purchase against defects in materials and workmanship (2016 and newer wheels), original owner, non transferable; decals and bearings two years (source)
- Certainty program — Five year warranty, lifetime crash replacement, 30 day trade out or return in the USA, replacement parts for any Rolf Prima wheel regardless of age, same day to 24 hour service replies, service work resolved within three days of receipt (source)
- Crash replacement — Lifetime crash repair or replacement discount for the original owner; wheels must be registered within 30 days of purchase; proof of purchase and serial numbers required; freight not covered (source)
- UCI approval — Non standard models (rims taller than 25 mm, fewer than 16 spokes) are listed on the UCI approval registry; Aspin and Elan are standard wheels that need no approval (source)
- Test standards — ISO 4210 used as the base with tougher in-house standards; impact test exceeds the UCI 40 J requirement; in-house drum fatigue, stiffness, brake and wind tunnel testing (source)
- Hand built in USA — All wheels hand built in Eugene, Oregon; each wheel built three times with two stress cycles; eleven patents (source)
Sources on Rolf Prima's site:
- Rolf Prima: Testing
- Rolf Prima: Paired Spoke Technology
- Rolf Prima: Our Technology
- Rolf Prima: Certainty Program
- Rolf Prima: Warranty
- Rolf Prima: FAQ (UCI, rider weight, build process)
Everything in this section is published by Rolf Prima. ProWheelBuilder is the seller, not the tester, and the wheel reaches you as the maker builds it.
A note on Rolf Prima
Rolf still fields service questions on Vector wheelsets with thirty years and more of riding on them. That is the practical case for a company that stayed in one place doing one thing: the wheel is older than a lot of bike shops and can still be sorted out.
Ordering it from ProWheelBuilder
Rolf Prima builds each Ares4 AR by hand to order in Eugene, Oregon. We sell it here at ProWheelBuilder in Georgia, confirm your axle and freehub selections when the order arrives, and can advise on the right driver if you are running SRAM road, SRAM AXS with an XDR cassette, or a Campagnolo group.
If you want the same carbon depth with a different hub brand, a higher spoke count or a specific lacing, we also build custom wheels on Astral rims, which is Rolf's rim brand. We are glad to quote both so you can decide whether the factory Ares4 AR or a custom build fits your riding better.
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. Because this wheelset comes assembled from its maker, the warranty that applies is theirs, set out above; ProWheelBuilder's one-year wheel warranty is for wheels we build here. Either way, a claim goes through us and we will manage it.
Full terms are on our Policies & Warranty page.
Ares4 AR questions
Is ProWheelBuilder the manufacturer of the Ares4 AR?
No. Rolf Prima designs and hand-builds the Ares4 AR in Eugene, Oregon. ProWheelBuilder sells it and handles your order.
How does the Ares4 AR differ from the Ares4 Disc?
The Ares4 AR uses a 40mm deep rim with a 25mm inner width for road and gravel tires. The Ares4 Disc is a 42mm rim with a 20mm inner width aimed at road tires. Both use XST 4.4 hubs.
Can I run the Ares4 AR on a Boost gravel frame?
Rolf lists 142x12 and 135 QR rear options only for the Ares4 AR. For Boost 148 look at the Hyalite Carbon or Vigor AR.
Does the Ares4 AR come tubeless ready?
Yes. It ships taped with valves. Rolf calls the rim tubeless-easy.
What is the weight of the Ares4 AR?
Rolf lists 1515 grams for the set, about 695 grams front and 815 grams rear.
Is 20 spokes enough for gravel?
For a fast all-road wheel, yes. Rolf's paired-spoke lacing lets 20 spokes carry higher balanced tension than a conventional 20-spoke wheel. Rolf backs it with a five-year warranty and lifetime crash replacement.
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 wheels for a living.
