Miche X2 RD R81 Ultegra Power Meter Chainring

X2 RD is the chainring designed for those who demand the maximum: lightweight, stiff, and capable of transferring every watt with absolute precision.

The R81 is designed for Ultegra 8100 cranksets with three dedicated configurations: 50, 52, and 54 teeth, while maintaining the same design philosophy.

Both are compatible with Miche R12 inner chainrings as well as original Shimano ones, giving riders different setups.

The essence of this chainring lies in its meticulous engineering and the incredible attention to detail we have always put into our products: a CNC-machined AL 7075-T6 aluminum plate merges with a structural 3K carbon layer, creating a unique synergy that delivers extreme stiffness, lightness, and top-level responsiveness in power transmission.

Specifications

• Weight: 126g
• Speed: 12cx
• Material: Carbon and AL 7075 T6/CNC
• PCD: 110
• Holes: 4
• Compatibility: Shimano Ultegra R8100

Every Watt Matters

• With X2 RD, it’s not just about pushing harder: it’s about maximising every single watt you produce, transforming energy into speed, and feeling the difference with every pedal stroke.
• Every watt saved is not just efficiency: it’s time, it’s performance, it’s results.

All UK Mainland Bike Deliveries Over £999 - Free Bike orders are sent via TNT/FedEx with estimated delivery within 1 working day after quoted dispatch time (For Scottish Highlands, Northern Ireland, Isle of Man and the Channel Islands deliveries please allow an additional 1-4 working days).Bike orders under £999 and eBikes will incur a £25 delivery fee.

Free Delivery On Orders Over £199.99 - When you spend more than £199.99 at 99 Bikes deliveries to a UK mainland address will be free (excludes bikes & large items).Certain regions and territories of the UK will incur additional charges, details of which can be found on our delivery page.

Click & Collect Orders -Please be aware Click & Collect orders may take some time to fulfil. We advise not to travel to your chosen store until you have been notified that your order is ready for collection.

At 99 Bikes our priority is to ensure that you are highly satisfied with your purchase. In the unlikely event that you aren't, we offer a 30 day online return policy* in which you can receive a full refund. Any item including bikes (with the exception of food) can be returned to us for any reason provided it is received by us in an unused and resalable condition in or with its original packaging which must be undamaged.

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