Reynolds Blacklabel 407 27.5" 157mm Wheelset

The Reynolds Blacklabel 407 27.5" 157mm Wheelset is built for riders who want to push the limits of what 27.5" wheels can do. With a 40mm internal rim width — among the widest in the Blacklabel mountain lineup — this wheelset is purpose-engineered for aggressive tire profiles on Super Boost-spaced enduro and trail bikes. When you need a mountain bike wheelset that won't back down from what you throw at it, the 407 delivers.

At the core of the 407 is Reynolds' MR5 construction process paired with their proprietary IDM (Impact Dispersing Matrix) technology. MR5 — Mountain Rim 5 — is Reynolds' approach to carbon mountain wheel construction, treating each structural zone of the rim individually and as part of a holistic system, balancing strength, durability, weight, and compliance across the entire rim profile. IDM takes it further: a carefully engineered combination of high-quality carbon fiber and a specialized resin with exceptional impact-dispersing characteristics. Originally developed for the rigors of World Cup downhill racing, IDM gives the 407 the ability to absorb and dissipate rock strikes and square-edge impacts that would compromise lesser wheels — without surrendering the low weight and ride feel you expect from a carbon rim. At 1,840 grams for the pair with full Industry Nine Hydra hubs, that weight figure represents serious performance for the category.

The rim's asymmetric, hookless profile completes the picture. Asymmetry equalizes spoke tension across the wheel, producing a stronger, more durable build with less variance between drive and non-drive side. The hookless bead seals tubeless tires with a clean, airtight interface that's resistant to burping under hard cornering loads. At 26mm deep, the rim profile stays nimble and light — rotational inertia in check on a wheel size where acceleration and handling feel are paramount. Each rim is laced to an Industry Nine Hydra hub with 28 Sapim CX-Ray bladed spokes. The CX-Ray is the benchmark for performance spokes, combining lateral stiffness with enough compliance to absorb trail chatter without fatiguing the rim joint. The I9 Hydra hubs deliver 0.52° of engagement — effectively instant power transfer — backed by a 6-pawl engagement system and CNC-machined precision throughout.

Design Benefits

1. 40mm internal width for maximum tire support: A wider rim creates a rounder tire cross-section that improves cornering traction, reduces sidewall squirm under load, and lets you run lower pressures without pinch flat risk. At 40mm internal, the 407 is optimized for 2.4" to 2.8" tires — the sweet spot for aggressive trail and enduro riding.
2. IDM carbon for proven impact resistance: Reynolds developed their Impact Dispersing Matrix on the World Cup downhill circuit. The result is a rim that holds up to rock strikes and compressions that would crack conventional carbon — without the weight penalty of aluminum and without sacrificing ride feel.
3. Industry Nine Hydra hubs for instant engagement: 0.52° of engagement means no lag between your pedal stroke and wheel response. On technical trail sections where power delivery timing matters — steep exits, off-camber accelerations — the Hydra hub is a genuine performance advantage over conventional freehub designs.
4. Asymmetric rim for a stronger wheel build: By offsetting the rim's spoke bed, Reynolds equalizes tension across all 28 spokes. A more evenly tensioned wheel is a stronger wheel — and one that holds true longer under repeated hard use.
5. Super Boost 157mm spacing for enduro compatibility: The 157mm rear hub spacing gives the 407 a wider axle stance, improving chainline and adding lateral stiffness. It's the standard spacing for enduro-oriented and plus-size frames, and the 407 is built specifically around that ecosystem.

Final Take

The Reynolds Blacklabel 407 27.5" 157mm Wheelset is not a product that hedges. It's built around a wide, IDM-reinforced carbon rim with the best hub and spoke combination Reynolds offers — sized for riders running aggressive 27.5" setups on enduro and wide-travel trail bikes. At 1,840 grams with I9 Hydra internals and Sapim CX-Ray spokes throughout, the 407 delivers the impact resistance and instant engagement that serious riders expect at this price point. If you're building around 157mm Super Boost and want a wheelset that matches the capability of the rest of your build, this is it.