Reynolds Blacklabel 347 27.5 Boost Wheelset

Reynolds built its reputation in mountain biking one race at a time, from enduro podiums to World Cup downhill courses, and the Reynolds Blacklabel 347 27.5 Boost Wheelset carries that DNA into a wide-trail carbon wheelset purpose-built for aggressive trail riding. The "347" name tells you what matters most: a 34mm internal rim width optimized for the 2.3–3.2" tire sizes that define modern trail riding, in a 27.5" diameter that excels on technical terrain where wheel diameter, nimble handling, and low center of gravity converge.

The rim is built around Reynolds' MR5 construction — Mountain Rim 5 — a process that applies five distinct carbon fiber matrixes across five critical zones in the rim structure. Rather than treating the rim as a single uniform layup, MR5 addresses the different structural requirements of the bead hook zone, the sidewall, the channel floor, the spoke bed, and the rim shelf individually, balancing strength, weight, compliance, and durability in each area as a holistic system. The result is a rim that can withstand the repeated rock strikes and lateral loads of trail riding without accumulating the micro-damage that leads to premature failure on lesser carbon constructions.

The rim profile is asymmetric and hookless. The asymmetric design offsets the spoke bed to equalize tension between the drive-side and non-drive-side spokes on the rear wheel — a geometry that produces a more uniformly tensioned, more laterally stable structure. The hookless bead profile is tubeless-ready by design, creating a secure, burp-resistant interface between rim and tire when properly seated. With a 34mm internal width, a 39mm outer width, and 25mm of rim depth, the 347 strikes a balance between the stiffness and traction benefits of wide rims and the low weight and handling responsiveness that trail riding demands. The total wheelset weighs 1,655 grams.

The hubs are Reynolds-designed and Industry Nine-manufactured Torch units — CNC machined with 3-degree engagement and a 6-pawl design built for reliable, repeatable power transfer on descents and out of corners. Industry Nine's Torch hub is a proven performer in mountain bike racing and trail riding at every level, with a bearing arrangement optimized for the combined lateral and axial loads of aggressive off-road use. Boost spacing — 110x15mm front and 148x12mm rear — provides the wider hub flange stance that improves wheel stiffness and spoke bracing angle on both ends. The freehub is available in Shimano HG, SRAM XD Driver, or SRAM Microspline to cover the full range of modern MTB drivetrains.

Sapim CX-Ray bladed spokes lace the rims at 28 front and 28 rear in a three-cross pattern. CX-Ray is Sapim's top-tier spoke — cold-worked to maximize tensile strength with a bladed profile that reduces aerodynamic drag and provides some lateral compliance under load. External alloy nipples keep tension adjustments accessible over the life of the wheel. The entire system is backed by Reynolds' lifetime rim warranty, a guarantee that reflects the brand's confidence in its own manufacturing and materials.

Design Benefits

1. MR5 five-zone carbon construction: Five distinct carbon fiber matrixes applied to five critical rim zones address the differing structural requirements of each area, producing a rim that balances trail-ready durability with low weight and compliance rather than trading one for the other.
2. 34mm internal width / asymmetric hookless profile: Wide enough to unlock the full performance of modern 2.3–3.2" trail tires, with an asymmetric spoke bed for even spoke tension and a hookless bead interface for secure tubeless fitment and inflation.
3. Reynolds/Industry Nine Torch hubs — 3° engagement: CNC machined, 6-pawl Torch hubs provide fast, consistent engagement for out-of-corner sprints and technical line corrections, with Boost flange spacing for improved wheel stiffness and spoke geometry.
4. Sapim CX-Ray bladed spokes: Reynolds' top-tier spoke choice across the Blacklabel mountain lineup — cold-worked for maximum tensile strength with a bladed profile that adds lateral compliance under impact loading.
5. Boost spacing: The 110x15mm front and 148x12mm rear standard improves hub flange stance and spoke bracing angles on both wheels, contributing to the lateral stiffness that makes the 347 feel planted under hard cornering.
6. Reynolds lifetime rim warranty: Backed by a lifetime guarantee to the original owner — a direct reflection of Reynolds' confidence in its own manufacturing process and material quality.

Final Take

The Reynolds Blacklabel 347 27.5 Boost Wheelset is a complete, race-validated carbon trail wheelset built for riders who want wide-rim performance, tubeless reliability, and I9 hub quality in a platform that Reynolds stands behind with a lifetime warranty. The 34mm internal width, MR5 carbon construction, and Torch hub engagement make a coherent performance case at $2,299.99 — a price that reflects what it actually costs to build a wheel this well.