Our conversion BB is designed to be a proper BB for Shimano™ Hollowtech cranks in either BB30, PF30, or Specialized's OSBB frames. Our patent pending design keeps the cartridge bearings outboard of the frame right on Shimano™ spec for greater rigidity and free of frame/c-clip tolerance issues that other systems deal with. Simply press in the longer non-drive-cup, then the shorter drive cup threads into it. As the drive cup threads in, our trademark Collet system expands to a precise limit evenly dispersing pressure for a super tight fit. With both cups connected and our collet set exactly to spec, there is no chance the bearings can come out of alignment or wiggle/walk out of the frame. This design also uses a compressible o-ring on the non-drive side cup to compensate for frame shell width discrepancies.
Our unique collet system also greatly reduces the chances for creaking and other unwanted noises associated with the lesser "Band Aid/Spacer" type adaptors in the market. The cartridge bearings are high quality steel with shield-type quad-ring seals. Available in either 68mm or 73mm widths, the Praxis Works Conversion BB is the most rock-solid BB for Shimano™ cranks on BB/PF30 frames.
"Praxis Works showed what we feel is the most thoroughly designed BB/PF30-to-24mm bottom bracket adapter currently on the market. The bottom bracket uses a collet system that wedges itself tightly inside the shell with even pressure throughout." —James Huang, Bike Radar