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Swiss Side Hadron² Ultimate 625 Disc review

Fast wheels get faster

Our rating 
4.5 out of 5 star rating 4.5
GBP £1,961.00 RRP | EUR €2,288.00
Swiss Side Hadron² Ultimate 625 Disc wheelset

Our review

Swiss Side confirms its aero pedigree with this confidence-inspiring wheelset
Pros: Fast and impressively stable wheels
Cons: Additional freehub body costs for some
Skip to view product specifications

Swiss Side claims its new Hadron² Ultimate 625 wheelset offers maximum aerodynamic performance with the widest operational range. That translates to being more usable over a broader range of terrain and conditions.


Available direct from Swiss Side, they come with tubeless tape and 12mm end caps installed, plus tubeless valves, valve extensions, quick-release end caps and skewers.

My test pair, including tape and end caps, weigh 777g on the front and 910g on the rear, totalling 1,687g.

The rims have a lifetime warranty against defects and measure 62.5mm deep, 30mm wide externally, and 20mm internally.

They’re built with 24 DT Swiss Aerolite II and Aerolite Comp II spokes on to DT Swiss 180 Dicut Centerlock hubs with SINC ceramic bearings.

The DT Swiss ‘pro lock’ aluminium nipples are hidden within the rims, which helps with aerodynamics but not maintenance.

The freehub body is Shimano/SRAM 11-speed, but if you’d prefer a SRAM XDR or Campagnolo one, you’ll have to pay €59 (circa £50) or €55 (£47) extra, respectively.

My 25mm Schwalbe Pro One tyres were easy to fit and seated immediately with a track pump. Finishing the tubeless setup was simple, with no pops or leaks and no fuss.

The tyres held air perfectly and measured 28mm wide when inflated. Swiss Side says these rims are optimised for minimum rolling resistance with 25mm and 28mm tyres, but are compatible with tyres up to a massive 64mm width.

Compared to the original Hadron, this Hadron² is claimed to reduce aero drag by around 15 per cent, and decrease the steering moment – turning force applied through the handlebar by air pressure acting on the front wheel – by 26 per cent, resulting in far greater stability.

While I can’t verify those claims, during testing, it was telling just how little I noticed the Hadron². Of all the similar depth wheels I’ve used, they’re the least affected by the elements, hugely increasing confidence when it’s gusty.

Their lateral stiffness makes for wheels that are more reactive than their mass might suggest.

They’re keen to accelerate and sustain high speeds on the flat and single-digit percentage gradients, and the additional tyre volume created allows lower pressures for increased grip and ride comfort.


I tested at 80psi or less, with no loss in speed, plenty of feedback and impressive real-world aerodynamics.

Product Specifications


Price EUR €2288.00GBP £1961.00
Weight 1,687g – tested pair, including tape and end caps
Brand Swiss side


Brake type Disc
Freehub Shimano/SRAM 11-speed
Hubs DT Swiss 180 Dicut centrelock
Rim depth 62.5
Rim internal width 20mm
Rim material Carbon
Spoke count 24 front, 24 rear
Spokes DT Swiss Aerolite II and Aerolite Comp II
Tubeless compatibility Tubeless ready
Tyre type Clincher
Wheel size 29in/700c