What is the function of SRAM XD Driver and XDR Driver?

SRAM hat die XDR- und XD-Driver entwickelt, um es uns zu ermöglichen, Kassetten mit Ritzeln von weniger als 11 Zähnen zu verwenden. Das ist großartig, wenn Sie eine 1x-Schaltung fahren möchten und trotzdem ein großes Kettenblatt haben möchten. Es wird dazu beitragen, das Erreichen der Höchstgeschwindigkeit zu verhindern, das einige von uns auf flachem Gelände hatten, und das viel wahrscheinlichere Erreichen der Höchstgeschwindigkeit beim Abstieg. 

Wenn Sie lieber ein Video zur Erklärung des XD- und XDR-Driver-Bodens sehen möchten, schauen Sie sich das SRAM-Video unten an.

The history of the XD driver floor

In 2015 SRAM brought us the XD driver to give us a 10 tooth sprocket. Using the 10-tooth sprocket allows cassettes to have a wider gear ratio, and it allowed SRAM to show that 1x11 arrangements and dual chainring arrangements can work. These days you can even find 9-tooth sprockets from some of the smaller, more specialized bike component manufacturers.

SRAM released XD with an open patent, so many companies jumped on the bandwagon and started making their own XD drivers. This was made easier by the fact that XD was designed to work with current axle designs and ratcheting mechanisms. The only major player that didn't participate is Shimano.

SRAM also states that the XD driver has advantages over a traditional freehub body. Your cassette will be less likely to wobble and cut into the freehub body on an XD driver. Because the freewheel is then more stable, you can expect the bearings to last longer.

What is the SRAM XDR?

The XDR is the street version of the aforementioned XD driver. It's designed to work on road-specific 11-speed wheels, so it's 1.85mm longer than the XD driver. It offers the same advantages as the XD Driver over traditional freehub bodies, and you should also save between 6 and 8 grams over a standard freehub body.

The best thing about both the XD and XDR drivers was that they saved us all from having to realign our wheels when we switched to a larger cassette. Spending less time in the workshop means we can all enjoy more time outside riding our bikes.

Do I need a SRAM XD driver or an XDR driver?

If you enjoy going off-road on a carbon mountain bike, you'll be looking for an XD driver. An XD driver takes up the same space as an 8,9,10 speed HyperGlide freehub body.

However, XDR drivers are intended for use on road, gravel and cyclocross bikes. It's just under 2mm longer than an XD driver and is designed to fit in the same location as an 11-speed HyperGlide freehub body. The easy way to remember the difference is that the "R" indicates that it is intended for road-based bikes.

The XDR driver can run 10-speed XD cassettes as long as you shim the cassette with a 1.85mm spacer.