Over the years drivetrain manufacturers have added more and more gears to rear cassettes, first seven speeds, then eight, then nine, now ten. To accommodate the wider cassette body that came with more gears, most wheel builders simply shoved the spokes in toward the center, shortening the spokes and increasing spoke tension on the driveside of the wheel to add what is known as "dish" to the wheel. Problem is, adding dish reduces the bracing angle of the driveside spokes, which in turn reduces lateral stiffness and weakens the wheel against lateral loads. The spoke tension is way up on the driveside, and way down on the non-driveside. That's a recipe for durability issues.

To avoid the pitfalls associated with traditional, center-drilled designs trying to accommodate expanding cassette dimensions, Bontrager uses OSB, which preserves spoke bracing angles and makes a much strong, stiffer wheel. Thanks to OSB, which comes with no additional weight penalty, spokes remain evenly tensioned on both sides, for greater longevity. OSB's an expensive feature. It basically doubles the amount of engineering we spend on every wheelset we make. Instead of sharing a single extrusion for the front and the rear of each wheelset, Bontrager invests in separate designs and extrusion for one simple reason: it makes for stronger, longer lasting wheels.