CeramicSpeed ​​OSPW RS 5 radios Shimano Dura-Ace 9250/Ultegra 8150

We recommend the 5-Spoke to riders who want real CeramicSpeed bearings on a Dura-Ace or Ultegra Di2 build without stretching for the Alpha version we also carry. The bearings inside are identical to what's in the pricier pulley — you're not giving up performance, just the solid disc and debris protection.

The open spoke design is worth being honest about. It picks up more road grit than a sealed Alpha pulley, especially riding through wet Brooklyn winters or on chip-seal roads upstate, so plan on pulling the pulleys for a cleaning or bearing check more often than you would with the Alpha. It's not a dealbreaker, just a maintenance rhythm to build in.

Weight and ride feel are close enough to the Alpha that most riders won't notice a difference on the bike — the gap between the two versions shows up in bearing longevity under bad conditions, not in how the drivetrain runs on a dry day.

We'd point this at a rider who rides mostly on clean roads and wants to save the difference in price, and steer someone doing a lot of wet-weather or gravel-adjacent road riding toward the Alpha instead.