SHIMANO ULTEGRA Di2 Shadow Rear derailleur helmet Aerodynamics or lightweight alone don’t

Aerodynamics or lightweight alone don’t win races - speed is what matters

and confident—all while helping reduce fatigue over long days in the saddle

which can boost mental performance

and reduce the chance of injury by optimizing hip

It helps add variety into your fueling without compromising the absorption rate of the carbohydrates

SHIMANO ULTEGRA Di2 Shadow Rear derailleur helmet Aerodynamics or lightweight alone don’tNow simplified with a single derailleur cage length, the new 12 speed Shimano ULTEGRA R8150 rear derailleur packs our fastest, most precise shifting into a more approachable option. With our fastest, most accurate shifting, the new 12 speed ULTEGRA R8150 rear derailleur is more versatile than ever thanks to a single cage length option that is compatible with 28 34T low sprockets. FEATURES Our fastest ever rear shifting, 58% faster than RD R9150