Ultegra SL HollowTech II chainset offers a fine balance of light weight and rigidity with incredible shifting performance.
- HollowTech II allows the bottom bracket bearings to be spaced wider apart (outboard the frame) enabling the use of larger bearings and an increased axle diameter
- There is also the benefit of easier installation , adjustment and maintenance
- Lightweight and rigid steel bottom bracket axle
- SG-X aluminium anodized chainrings available in 53-39T / 52-39T (FC-6600 double), 52-39-30T (FC-6603 triple) and 50-34T (FC-6650 compact)
- Available in 165 mm, 170 mm, 172.5 mm and 175 mm
- Aluminium chainring bolts
- Weight 797 g (53 / 39T, 170 mm including bottom bracket)