Oversized ceramic pulley systems are an excellent way of reducing the additional friction caused by clutch derailleurs.

Kolossos is the Greek word for a statue, much larger than the original subject. Seems fitting for an oversized derailleur cage.

Imagine the performance of replacing your stock pulleys with a ceramic 12-tooth top pulley and a 19-tooth bottom pulley built on the stiffest cage on the market.

Besides reduced friction, this cage is built with shifting accuracy and chain retention in mind. Kogel Bearings has always had a strong connection to off-road disciplines. We wouldn't build it if it weren't gravel proof.

This model is built for the GRX 2X (11 and 12 speed) and Ultegra RX800 series derailleurs. This includes mechanical and Di2.

For GRX 1x set ups, we recommend the GRX 12 speed 1x Kolossos

Please note** Installing this oversized derailleur cage typically requires replacing your chain to accommodate the larger pulleys on. a2x setup.