Hollowtech II works with 24 mm axles bearings. This gives the greatest possible balance of rotation efficiency, rigidity, strength, and weight in the proven Shimano quality.

SPECIFICATIONS:

Application: Road
Series: Dura Ace R9100
Type: BSA or ITA
Shell Width: 68 mm (BSA) or 70 mm (ITA)
Axle Diameter: 24 mm (Hollowtech II)

TECHNICAL INFORMATION:

Bearings: Steel
Bottom Bracket Cup Material: Aluminium

FEATURES:

– small ball bearings keep weight low
– bearing cups anodized
– recommended for Dura Ace FC-R9100, FC-R9100-P, FC-9000

TECHNOLOGY:

Hollowtech II
The outboard bearings offer better weight distribution and more stability that provides a more efficient power transfer. The diameter of the bearing axle (24 mm) was an important factor in development because the axle has a positive effect on stiffness, stability, weight, and rotating efficiency.

FACTORY NUMBERS:

BSA: I-BBR9100B
ITA: I-BBR9100I

CONTENTS

– 1 x Shimano Dura Ace BB-R9100 right bearing cup, bearings included
– 1 x Shimano Dura Ace BB-R9100 left bearing shell, bearings included
– 1 x Shimano bottom bracket shell