DT Swiss RC38 Spline C DB wheels review

Disc-braked carbon clinchers

Our rating 
3.0 out of 5 star rating 3.0
GBP £1,329.98 RRP | USD $2,068.00
DT Swiss RC38 Spline C DB wheels

Our review

DT’s wheelset wrings a lot out of its design, but we’d like to see more
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DT Swiss wheels are often found as original equipment on road bikes – sometimes rebadged with another brand’s name – so it’s nice to be able to try out a set that are unashamedly DT.

  • Highs: Light, fast, convenient, fine hubs
  • Lows: Internal nipples, narrow rim width

The name ‘RC38 Spline C DB’ breaks down to Road Carbon 38mm, with a Spline hub and Clincher rim, designed for Disc Brakes. What that means for us is a mid-height carbon clincher rim without a braking track. Current thinking dictates that road disc wheels need at least 24 crossed spokes, and the DTs have exactly that, with double-butted straight pull spokes laced two cross, front and rear. This arrangement resists the hub deceleration from disc use that would pull a radially spoked wheel apart.

The Spline hub design seats each spoke at the optimum angle to the rim, placing the minimum amount of stress on the hub bearings. They are designed to accept CenterLock splined disc rotors, but an adaptor for six bolt ISIS rotors is also included. Without rim tape (17g) or skewers (50g, 56g), our test pair weighed 680g for the front and 800g for the rear, which is respectable, although you’d need to add rotors too.

Light they may be, but the RC38s don’t follow modern ideas for rim width, measuring 21mm maximum. Our 25mm tyres fitted well, and DT Swiss recommends a 28mm limit, which would take on more of a light bulb profile.

The low mass makes them lively performers, proving willing to accelerate and keen to sustain speed. Handling is precise, though crosswind stability is less than a similar depth rim that’s several millimetres wider.

Hard braking doesn’t fluster these wheels, and ride quality – even over rough stuff – is very good. DT Swiss rates the RC38s as most suitable for flat or mixed terrain, some racing but less cyclo-cross, so does it know something we don’t?


We found them fine on hard-pack gravel and fast road riding, but for more extreme use, the hidden spoke nipples are a long-term maintenance challenge, though the necessary tools are provided.

Product Specifications


Name RC38 Spline C DB (14)
Brand DT Swiss

Front Wheel Weight 680
Front Wheel Weight (kg) 0.68
Rear Wheel Weight 800
Rear Wheel Weight (kg) 0.8
Rim Description Clincher Rim