Each rim of the Sun Ringle Duroc 37 pro wheels is 37mm wide (32mm internal) with 28 straight-pull Wheelsmith double-butted spokes. They come fully taped ready for tubeless with valves installed, with two bottles of sealant, and both SRAM XD and Shimano freehub bodies.

Read more: Best mountain bike wheels in 2020 – aluminium and carbon options

The new freehub offers a clever design called Clock’d that allows the pawls to be orientated in two different ways. First, you can line up all six simultaneously for maximum strength, or offset those pawls into the hub’s ratchet ring so three engage at any one time. The latter way increases pick-up speed and halves engagement to just 4°. It’s a neat solution for an ultra-durable or faster engaging hub, as you prefer.

With the hub set to its faster engagement I had zero issues with crunching, slipping or pick-up over months of testing. The hub body, flanges and freehub all appear high quality although I did have one issue – the included stiffness-boosting Torque Cap adaptors bound together and wouldn’t work with my RockShox Zeb. The wheels spun freely with standard end caps, so this wasn’t an issue for testing, but Torque Caps deliver noticeably more steering precision and I’d prefer to use them.

The joint-welded, reasonably shallow, Düroc rims are 597g each, designed to be tough and rated for the “gnarliest descents at the fastest speeds you can muster.” Despite the complete wheelset being north of two kilos, rolling speed and acceleration are decent and there’s more tightness and snappiness than many wheels 
of similar weight.

Dented rims suggest the Duroc are less than bombproof

On proper Alpine tracks underneath a long-travel 29er the Dürocs are plenty stiff enough, even through massive bike park berms, side-load G-outs, rock gardens and horrible root webs. They’re also comfortable and calm with no sharpness or excessive twang evident.

However, on a 10-day trip to the Alps this summer, running latest thick-casing heavyweight Michelin Comp 34 tyres, I still put multiple big dings and dents in Sun Ringlé’s rims. They did get a proper hammering, including big bike-park jumps and multiple heavy cases, but I’ve used a wide variety of wheels over the last few years on this kind of trip, both carbon and aluminium, with better results. The wheels remained true and spoke tensioning tight though, so impacts from rocks and square edges at speed were the cause of the damage.

This could just be bad luck, but I don’t think so – I’m not overly heavy on wheels and multiple similar trips on other rims have caused zero damage. In our riding group we were also swapping between bikes, with the Sun Ringle Duroc 37 Pro wheels being the only wheels dented in this way. So while the ride quality is sorted, I’ve had better luck with rim hardness and ding-resistance, even on significantly lighter wheels.