Shimano’s updated their outboard and press fit bottom brackets, too. The bearings inside are smaller and the actual size of the external cup is smaller and lighter. The biggest improvement is in the sealing. They’re able to maintain the same sealing but with 50% of the resistance.
“For us, we believe that steel is the optimal material for the spindle and BB30 is really optimized for an alloy spindle and carbon crankarm,” said Lawrence. “We’re pretty committed to steel and aluminum arms and the 24mm spindle in steel is the best solution for us.”
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