The Shimano Ultegra R8170 disc wheelset is a carbon tubeless road wheelset with a wide internal rim width designed to be used with tubeless tyres.

On test here in its 50mm-deep variant, it sits below Shimano’s top-tier Dura-Ace range, maintaining many of the performance benefits at a lower price.

Shimano Ultegra R8170 wheelset key specs

Weight: Claimed 1,570g, measured 1,607g including tubeless tape (no valves)Size: 700cFreehub options: Shimano HGRim depth(s): 35, 50, 60mmRim internal width: 21mmSpoke count F/R: 24, Rear 2:1Spoke type: Bladed straight-pullRim material: Carbon Fully set up tubeless or tubeless-ready? Fully tubeless

Shimano Ultegra R8170 wheelset rim width and profile

The rim profile of the Shimano Ultegra R8170 wheelset is identical to that of its higher-priced, lighter-weight Dura-Ace counterpart and Shimano claims that at yaw angles from 0 to 15 degrees, their rim profile reduces drag better than other aero shape rims. However, the brand doesn’t specify exactly which competitors they’re being measured against.

Shimano has opted for a modern 21mm internal rim width, which will pair well with 28mm tyres, and provides sufficient sidewall support to stop the tyre from rolling in corners.

While many big players in the aftermarket wheel world have made the move towards hookless rims, citing the benefit of a smoother transition from rim to tyre resulting in improved aerodynamic efficiency, Shimano has opted to play it safe and stuck with a hooked bead.

I am a fan of hookless rims and would have liked to see them here, but many riders will appreciate the freedom of tyre choice a hooked rim offers.

Shimano Ultegra R8170 wheelset lacing pattern

Both wheels use 24 straight-pull bladed spokes, the front wheel sticks to a conventional 2x lacing pattern, whereas the rear is built using what Shimano call ‘OPTBAL’ lacing, more commonly known as 2:1, in which there are 16 3x laced spokes on the drive side of the rear wheel, and 8 radially laced on the non-drive side.

This pattern has long been utilised by Campagnolo in wheels such as the Bora Ultra and works well to address the tension imbalance inherent in rear wheels. The Ultegra R8170 wheelset certainly feels stiff under load, particularly when sprinting or climbing hard.

The downside to this level of proprietary equipment comes in future serviceability. Proprietary spokes are more expensive and may be harder to source in an emergency, and a 2:1 rim cannot be laced to a traditional hub, and vice versa.

Provided proper maintenance is kept up, this shouldn’t be an issue, but if you’re a rider prone to neglecting and destroying hubs, it may be worth consideration.

Shimano Ultegra R8170 wheelset build quality

On inspecting build quality I have found the R8170’s to be true to within 0.5mm both radially and laterally, built to even tension, and perfectly in dish. This is to be expected at this price level, but it’s good to know that Shimano isn’t cutting corners on build quality.

The rims themselves are painted, which makes it difficult to assess any visual variances in the carbon fibre, however the rim bed does not show any signs of inconsistency, with no sharp areas or obvious flaws.

They were tubeless taped out of the box, and quick and easy to set up tubeless with the use of an Airshot, and using 30mm Schwalbe Pro One tyres.

Shimano Ultegra R8170 wheelset alternatives

I’ve been testing these wheels in the 50mm option, but they are also available in 35mm and 60mm depth options, all with the same 21mm internal width. For the all-rounders, 50mm is a great depth to go for, offering a middle-ground of aerodynamic efficiency without sacrificing handling or feeling heavy.

I measured the Ultegra R8170 wheelset at 1,607g with tubeless tape installed. This is 37g heavier than the claimed 1,570g, however rim tape accounts for approximately 25g of this difference.

Some competitors’ wheelsets such as Hunt’s 50 Carbon Disc SL come in over 100g lighter but achieve this using smaller hub bearings, which tend to trade off some long-term durability.

Shimano Ultegra R8170 hubs

The Ultegra R8170 hubs use their own large and well-sealed bearings, which did not show any signs of water ingress despite the majority of my testing being in wet conditions.

Based on previous experience with Shimano hubs I’ve found them to run well for many years provided they are serviced correctly.

It’s easy to question the adage ‘with weight comes reliability’ but there is no questioning the benefits of a larger bearing. Shimano has long stuck by the cup and cone bearing rather than switching to more commonly used cartridge bearings.

This allows the brand to use a combination of relatively large 5/32 and 3/16in ball bearings, and facilitates a thorough level of bearing service without replacing parts.

Freehub engagement is relatively low at 20 degrees, however it’s a common misconception that a high engagement angle is a necessity for road wheels, where the freehub is engaged the majority of the time.

A lower number of engagement points typically results in improved reliability and a reduced chance of slipping under load. Typically, Shimano has stuck with the reliable option here.

Shimano Ultegra R8170 wheelset serviceability

Service is a simple procedure for a competent home mechanic, and minimal tools are required. An adjustable preload also allows bearing wear to be compensated for, rather than replacements being required. In a world of increasingly throwaway parts, I’m pleased to see Shimano sticking with cup and cone bearings, and would expect these hubs to last many years provided they are serviced as required.

Spoke replacement requires basic tools but spokes are proprietary and may be harder to source in an emergency than more standard options from Sapim or DT Swiss.

As with all Shimano products, technical documents and full-service instructions are easy to find on the brand’s website.

Shimano Ultegra R8170 wheelset ride feel

On the road, the R8170 C50 wheelset feels lighter than the numbers would have you believe and reacts well to changes in pace. I’m putting this down to the weight being concentrated at the hub. When sprinting there is no discernible flex in these wheels, they feel very stiff, so much so that I dropped a couple of psi from my usual tyre pressures to keep a comfortable ride.

The bearings have remained exceptionally smooth despite several weeks of riding in very wet conditions, and the freehub has the characteristic near-silent click we’ve come to expect from Shimano.

I find this refreshing when so many competitors’ wheels are extremely loud. The racers will appreciate being able to stealthily move about the bunch, and leisure riders will enjoy the sounds of the countryside uninhibited by an obnoxiously lairy freehub.

When riding in high winds there is no escaping the 50mm depth of these wheels, and I did feel the wind tugging at them on occasion, but they don’t feel any more unstable than you would expect from similarly deep competitors. Riders concerned about handling in the wind would be advised to opt for the 35mm version.

Shimano Ultegra R8170 wheelset verdict

It’s great to see Shimano updating its traditionally conservative wheel offering, and the resulting product is well worthy of the Ultegra name. The performance offered by the Shimano Ultegra R8170 C50 wheelset is difficult to fault, and they offer a great value aero upgrade compared to their identically profiled Dura-Ace counterparts.

Weight weenies may wish to look elsewhere, however for the sake of 100g or so most riders will benefit from the reliability of the larger bearings and easily serviceable hubs, and those with a larger budget would do well to consider the Dura-Ace alternative for a claimed 109g weight saving.

Looking for more wheel reviews? Read our Hunt 48 Limitless review

Photography: Rob Borek