HOLLOWcage® for Shimano Ultegra 8100 12spd. Our revolutionary mono-plate OSPW design is the quietest and best shifting, oversized derailleur cage for Shimano 12spd created to date. HOLLOWcage ® OSPW has a carbon-polymer mono-plate construction with bespoke, oversized, full ceramic bearings and the most advanced silencing pulleys ever made.

THE NEW ERA OF SILENT PULLEYS. MEET THE SILENT XRING PULLEY™
Does it bother you when you ride in a really quiet scenery but you can still hear your bike’s chain engaging the pulleys? This familiar clunking noise has been accompanying us on every ride for decades. It’s time for a change.
Common polymer pulleys are fairly loud, this has always been a norm. Aluminium pulleys are even worse as the material radiates the sound more than any polymer, making them louder. We are introducing a completely new generation of pulleys, which are able to reduce the sound level by 5-7dB when compared to stock Ultegra pulleys. This corresponds to roughly 40% of the noise reduction. Practically speaking, the cage becomes very silent.We use a patent pending solution, our special xring rubber suspended bands, that dampen the chain impact on the guide pulley teeth, therefore eliminating the engagement noise, which is the single biggest contributor to overall drivetrain noise. From now on, your ride is going to be more silent than it used to be and you will hear sounds that you haven’t noticed before. It's the new era of derailleur cages

WHY IS OUR HOLLOWCAGE® SO SPECIAL?

• It is super silent (over 5dB noise reduction vs stock).
• The shifting is as good as with the original Dura Ace cage.
• One of the lightest oversized cages on the market.
• First mono plate construction of its kind.

Specifications
Colour: Lower lockring Rainbow
Compatibility: Shimano Ultegra 8150 12spd ONLY. Fits up to 34T cassette.
Materials used: Carbon fiber-polymer matrix, 7075 Aluminium, rubber, ceramics
In the box: Complete cage, lockring tool, 2x spare xring rubbers
Designed in England
Manufactured in EU

Mfr Claimed Weight
71g

Installation

Please refer to the video instruction below. You should mount the cage with the lowest spring tension setting (First hole from left). If you use 11-32T cassette in combination with 52/36T chainrings or bigger you may need to set the cage with higher spring tension setting (the original tension hole) to account for the chain growth, but only if first position produces loose chain in small - small gear.
For service / maintenance instructions please refer to our FAQ page.In the video below you will also find how to determine the correct chain length for your HOLLOWcage. Following this tutorial is crucial for the proper functioning of the drivetrain.