Partington R-Series MKII R39/44 review

The Australian-designed Partington R-Series MKII R39/44 wheels carry the claim of being the lightest tubeless-compatible clincher wheelset in the world.

Ultra-light weight and true aerodynamics are not usually considered good bedfellows, however the R-Series begs to differ.

So, does the performance match the headlining-grabbing stats and fascinatingly original design?

Partington R-Series MKII R39/44 specifications

With a claimed weight of only 1,160g for a disc-brake wheelset, my test set tipped the scales at 664g for the rear and 554g for the front (including valves).

Ready for tubeless tyre installation, 1,218g is remarkably light, especially when you consider these don’t exhibit a shallow depth like a lightweight climber’s wheel.

The R-Series can certainly be thought of as an aero-optimised all-rounder wheelset, combining a 39mm-deep, 26.5mm-wide (21mm internal) front rim and a 44mm-deep, 26.5mm-wide (21mm internal) rear rim.

Partington builds its wheels very differently too. The all-carbon hubs forgo traditional flanges with spoke holes. Instead, the hub flanges are channelled to lock in the unique V-shaped ‘in-tension’ spoke design.

The individual spokes hook around and lock into the hub (one spoke is in fact two as it proceeds outwards on the other side). These are attached and tension-adjusted with traditional spoke nipples at the rim.

Partington claims this makes for an even load distribution and contributes to the R-Series being one of the most laterally stiff road bike wheelsets available.

Partington says these are produced using a proprietary process – a single spoke is said to be made from 108,000 continuous filaments.

The rims are made with moulded inserts for the unique spokes and laid up around a foam core that stays in place. It’s a similar process to how Corima builds its carbon rims and is said to confer structural benefits as well as ride-quality improvements.

The tyre bed of the rim is smooth and undrilled, so tyres seal without the need for messy tape or the risk of unwanted leaks.

Partington R-Series MKII R39/44 ride impressions

I tested the R-Series with 28c Pirelli Cinturato tyres, reflecting the early-spring conditions.

These aren’t particularly voluminous tyres, coming up just under 28mm wide on the rims. However, with an external width of 26.5mm, the rims are ideally suited to similar-width tyres.

At 1,218g a pair, the R-Series wheels have an immediate effect on how your bike feels. The Partingtons replaced the already lightweight Black Inc 5s on my Cannondale SuperSix Evo, and while the near-200g weight saving doesn’t seem like a huge amount, it's noticeable when heading uphill.

The R-Series makes a real difference in how impressive the lateral stiffness is.

These feel like the Black Incs and Cadex 42s in that respect, and like both those radical wheel designs, the R-Series also has carbon as the spoke material.

Even though the R-Series wheels feel stiff, they aren’t uncomfortable with it. The responsive feel under power impresses, but over broken road surfaces or traffic-calming humps, the wheels feel impressively compliant.

The smoothness of the ride is matched by the slick hubs, which are designed and manufactured in-house.

Because of the unique spoking configuration, the hub’s architecture isn’t limited by traditional flanges. That has enabled Partington to reposition the bearing location.

Partington calls the bearing fitment a ‘floating’ design, which it claims minimises the load and stresses, thereby ensuring smooth spinning and minimal energy losses under different loads – according to Partington’s white paper on the hub design.

For example, when the bike is moving in a purely upright position, the bearings are in a neutral axial position – this yields the lowest internal load and therefore the lowest-friction conditions. Under axial loads (cornering, climbing, descending) the forces acting on the bearings change, but the effect of this is said to be minimised here.

Partington uses a deep-groove design for the bearing races, with differential sizing, and combines this with asymmetric positioning of the bearing assemblies within the hubs. The ball bearings themselves (as you’d imagine on a premium wheelset) are ceramic, from specialists CeramicSpeed.

The freehub has 42 teeth for a quick 8.57-degree point of engagement – a good match for how smooth the hubs spin and the overall feel of luxury the Mark II R-Series wheels exude.

Partington R-Series MKII R39/44 bottom line

These wheels are undoubtedly some of the very best I've tried. They’re as responsive as Cadex’s excellent 42 wheelset and lighter than Zipp’s also-excellent 353 NSWs.

The elephant in the room, however, is that £5,500 / $6,400 / €7,300 price tag. It’s a full £2,300 more than the 353 NSW, and more than double the price of Cadex’s 42s. Only Lightweight’s (70g heavier) Obermayer Evo wheelset outstrips them on price (an eye-watering £7,060 / $8,095 / €6,505).

Overall, the Partingtons are a fascinating design, with fabulous performance to boot, and sit at the top of my desirability list.

That said, I and the vast majority of others will never be able to afford them, while it’s fair to say there are ‘top-spec’ wheelsets out there that almost equal the performance for much less money.