The overall power savings of the OSPW System for Shimano 9100/9150 /8000 reach 30%-60%, or more in some cases, over a stock setup.
The oversized pulley wheels have 3-5 times longer lifetime than the commonly used standard pulleys on the market.
The 9100/8000 system is not compatible with Ultegra 8000-GS (long cage) or clutch equipped Ultegra RD RX800 & RX805. Please see our Shimano 11 Speed Pulley Wheels for a compatible upgrade.
The Shimano 9100/9150 and 8000 SS/8050 SS OSPW system is compatible up to a 32 tooth cassette for both Dura Ace & Ultegra derailluers.