Delivery in 4-5 business days (Europe)
Bigger is faster. Large derailleur pulleys cause less chain deflection and slower rotation of the ceramic bearings. Both lead to less friction and more efficient power transfer.
Main advantages
- Reduced friction while maintaining shifting accuracy
- Kolossos is 3x stiffer than competing products and 2x stiffer than the original pulley cage on your derailleur
- Long tooth profile on the lower pulley for better chain grip
- Ceramic bearings in the pulleys for even lower friction
- Choice of three colour options
Compatibility: Shimano GRX (RD-RX810) and Ultegra RX800 gravel derailleurs, mechanical and Di2. This cage also fits the GRX 1x derailleur (RD-RX812) and allows shifting across the full 11-42 cassette range, but leaves a large gap between the top pulley and the smaller cogs, so expect less snappy shifting in the last three gears. Pulleys: 12 teeth (upper) and 19 teeth (lower).
