
24mm Diameter Axle And Bearings
Why choose the 24mm axle and bearings for the HOLLOWTECH II crankset?
The diameter of the Bottom Bracket axle and bearings was of primary importance for the development because the Bottom Bracket axle area is tied to such key elements as stiffness, strength, weight and rotating performance.

Bending rigidity/
breakage
Rotating
performance
Torsion rigidity/
breakage
Weight of axle/
bearings
What’s important is the total balance of crankset
In addition, taking the crankset as a whole, the total balance of crankarm rigidity, axle stiffness, bearing position and others is essential.
Indeed, the crankset is designed by careful consideration of the total balance of those elements to prevent breakage.
Outboard Bearing
For most frames with 68mm Bottom Bracket shells, HOLLOWTECH II with 24mm axle can set the bearing position outside of the frame to provide better weight distribution and more stability.

24mm Diameter Axle And Bearings Provide Optimum Balance For The Crankset
After studying all these problems thoroughly, we made the decision to adopt the 24mm diameter axle and bearings, which have the optimum balance, for the HOLLOWTECH II crankset.
In addition, an examination of the total crankset, including the crankarm and gears, proves the optimum balance of rigidity, weight and rotating performance for the ultimate transfer of power to your bike. HOLLOWTECH II is simply the most optimized crankset design on the market.