There’s been a lot of talk about wider gravel tires recently. Sure, the larger contact patches may yield better grip, but what about aerodynamic drag and increased weight?
Well, thanks to a partnership with Stromm, WTB has introduced three new high-volume gravel tires that are pretty light and up substantially faster in the wind tunnel.
The new collection is engineered for wide gravel rim compatibility (25–32mm internal width), with tread and sidewall profiles optimized around a 28mm internal width. Construction centers on a 120 TPI casing with bead-to-bead SG2 puncture protection and a Dual DNA rubber compound featuring a harder center compound for decreased rolling resistance and a softer shoulder compound for increased grip.
The defining technical feature across all three models is a patent-pending aerodynamic treatment incorporated into the sidewalls: trip strips and vortex generators designed to manipulate airflow over the tire and wheel system, which controls boundary layer separation and reduces the low-pressure wake that would usually increase drag which slows you down.
Stromm validated the design at the Jerry Baker Memorial Velodrome in Redmond, WA. Measured drag reductions compared to an identical control tire without aerodynamic features were 5.8 watts at 30 km/h, 9.3 watts at 35 km/h, and 13.8 watts at 40 km/h. Notably, tires were tested both clean and dirty to make sure these aero benefits would actually carry over once the tire touches dirt in the real world. Want to read more? Check out the Stromm aero gravel tire white paper below:
Tire Models
The three models are differentiated by tread profile and intended terrain as well as size. Currently, each model is only offered in one size, and the tires get more aggressive in tread as they get larger. Note that each tire is 10g heavier for the claimed weight on the black sidewall version.
Byway RS 50
The Byway RS 50 features a slick centerline with low-profile shoulder knobs suited to hardpack and paved surfaces. At 620g claimed, this one actually came in at 613g.
- 50mm section width
- SG2 bead-to-bead protection available in both black and tan 120tpi casing options
- The slick centerline delivers exceptional rolling efficiency
- Low profile intermediate and shoulder knobs offer predictable cornering when leaning over
- Round tread profile to allow smooth cornering on hard pack and loose terrain
- Patent-pending aerodynamic technology to help conserve energy at speed
- 100% Recycled packaging
Course 52
The Course 52 uses a multi-condition tread pattern at a claimed 635g, though ours weighed 662g and 644g.
- 52mm section width
- SG2 bead-to-bead protection available in both black and tan 120tpi casing options
- Versatile tread pattern delivers dependable traction without sacrificing efficiency
- Tightly placed center tread grouping to aid in rolling speed
- Round tread profile to allow smooth cornering on hard pack and loose terrain
- Patent-pending aerodynamic technology to help conserve energy at speed
- 100% Recycled packaging
Macro 54
The Macro 54 carries taller, wider-spaced knobs for loose and technical terrain. Oddly, the Macro has the highest claimed weight of 640g, but one of ours came in the lightest of all three tires at 612g. The other Macro was 634g, still lighter than both of the Course 52 tires.
- 54mm section width
- SG2 bead-to-bead protection available in both black and tan 120tpi casing options
- High volume for rougher terrain and bigger adventures
- Aggressive tread for maximum confidence on loose, rocky and technical terrain
- Widely spaced transition and side knobs to provide increased cornering traction
- Patent-pending aerodynamic technology to help conserve energy at speed
- 100% Recycled packaging
All three are available in black or tan sidewalls at an MSRP of $89.95 each through WTB’s dealer network and wtb.com.
First Impressions
To get a feel for the new tires, I threw the Byway RS 50s on a set of Reserve 40/44 gravel wheels which have an internal width of 27.4/27mm. After a few weeks and some stretching, the 50mm tires measure over 52mm wide, so keep that in mind if your clearance is tight. Starting at 30 psi, I eventually let some air out to make them a bit more supple.
Coming from a set of 45mm WTB Vulpine S tires, the Byway RS feels like it has a faster center section with smoother transition from the center to the shoulders. I would be lying if I said I felt any aerodynamic improvements, but the tires do feel very fast. I’d say they’re the fastest tires I’ve tried over 50mm wide, but then again, that’s a very short list.
It’s been an extremely wet summer here, so I’ve been spending a lot more time on pavement and hardpack gravel (hence the Byway RS choice), but I’m looking forward to some more dirt/gravel adventures to get a feel for the new Course and Macro tires.
