Shimano CentreLock disc brake nut SM-RT81 - Y8K198010

Shimano ’s CenterLock SM-RT81 clamping nut, part number Y8K198010, is a replacement part designed to secure Shimano brake discs fitted with the CenterLock system. It secures the disc firmly to the hub via an internal clamping system and is the ideal solution for replacing a lost, damaged or worn nut.

Made from aluminium, this Shimano clamping nut is supplied with a washer and has a black finish. Part number Y8K198010 corresponds to the ‘Lock Ring & Washer’ assembly identified in the Shimano documentation.

A Shimano nut designed for the CenterLock system

The Shimano CentreLock system allows a brake disc to be quickly secured to a compatible hub. Unlike a 6-hole disc, the CentreLock rotor is positioned over central splines and then held in place by a lock ring.

Part number Y8K198010 features an internal spline and is fitted using a cassette removal tool, such as the Shimano TL-LR15. This design allows you to use a tool already available in the workshop for drivetrain and brake maintenance.

Shimano SM-RT81 Compatibility

This clamping nut is specifically listed for the Shimano SM-RT81 CenterLock disc. The documentation at Shimano confirms part number Y8K198010 as the disc mounting part, with compatibility also documented for several Shimano braking systems using the SM-RT81 rotor.

It is particularly suitable for set-ups fitted with a quick-release mechanism or a 12 mm thru-axle, with an internal tool mount.

Technical specifications

• Brand: Shimano

• Manufacturer’s part number: Y8K198010

• Related part number: SM-RT81

• Type: CentreLock nut / clamping ring

• Application: brake disc mounting

• Mounting: CentreLock

• Clamping type: internal

• Material: aluminium

• Colour: black

• Grooves: internal

• Installation tool: cassette removal tool / Shimano TL-LR15

• Recommended tightening torque: up to 40 Nm according to the available technical data sheets

• Supplied with: washer

• EAN: 4524667956259