Shimano GRX RD-RX815 Di2 11 Speed Shadow+ Rear Derailleur
- ShowProduct Information Instead of telling gravel riders what they needed, we asked them what they wanted. Shimano spent two... read more
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Instead of telling gravel riders what they needed, we asked them what they wanted. Shimano spent two years listening and countless hours speaking with gravel enthusiasts from all over the world. We took to dirt and gravel roads, narrow singletrack paths, creek crossings, and mountain passes to test ourselves and our notions of drop bar cycling. We pinned on race numbers and packed up bikepacking bags. We choked on dust and reveled in mud. And the result of all that riding and all those new friendships? First, Shimano’s Gravel Alliance and now, Shimano GRX, the world’s first dedicated gravel component series.
Choice. Shimano’s new GRX line is all about choice. Shimano doesn’t want to pigeonhole the way you ride, or decide for you what the best solution is for your riding style. While we’ve long been fans of double chainring drivetrains, we also recognize the value of a single chainring system. With GRX, Shimano offers both, each with gearing options that allow you to tailor your drivetrain to suit your tastes.
With two different derailleur cage lengths, Shimano GRX ensures stable shifting and chain retention across a wide range of gearing options. Looking for maximum range while maintaining road cassette progression? Go with GRX’s 800 series 2x11 RD-RX810 or Di2 RD- RX815 rear derailleurs, designed for close ratio clusters, with 48/31 chainrings and an 11-34 cassette. Paired with 700c x 40mm tires, it delivers a top gear similar to a road bike with 25mm tires and a 50 x 11 gear. And on the low end, with its 31 x 34 combination, you get a gear that early mountain bikers would envy. It is the lowest gear currently on offer for premium road drivetrains (aside from Shimano’s own GRX 2x10 30-36 offering), perfect for climbing loose, dirt and gravel surfaces.
Want to drop some weight, simplify your shifting, and still maintain a versatile range? Consider the 1x11 GRX option with either Shimano’s 11-40 or 11-42 cassette and a 40 or 42-tooth equipped crankset, shifted by a RD-RX812 or Di2 RD-RX817 wide ratio rear derailleur. You’ll lose a little, absolute top speed, but still love the 1:1 low gear ratio. If you live in an area without sustained or steep climbs, you might love the smaller gear steps of that same 1x11 front chainring with an 11-34 cassette. Options abound.
What about when the weather turns autumnal and you contract a case of cyclocross fever? GRX 1x11 can quickly transform from gravel fun to CX focused with the change of a cassette.
No matter the option you select, GRX rear derailleur offerings feature Shimano’s SHADOW Plus chain stabilizer that can be turned on or off depending on conditions. SHADOW Plus revolutionized the mountain bike world and now it’s been tuned for gravel and rough road riding in GRX. With a quieter drivetrain, SHADOW Plus helps you engage with your surroundings and enjoy time outside.
Today’s gravel riders demand more of their bikes and of themselves. Shimano GRX gives them the options they need to Explore Beyond, tailoring their drivetrains to suit their needs and exceed their expectations. We’ll see you out there!
Designed for riding on rough roads, through gravel and mud, to be able to carry on in comfort, stress-free, to wherever you want, to allow you to achieve that unique sense of accomplishment. The first groupset designed for Gravel riding Explore beyond. Introducing SHIMANO GRX.
Even on the roads less travelled, our new GRX tech will keep things smooth, silent and safe – with you always in control.
Designed from the ground up for gravel adventure.
Mix and match components to customise your bike for a wide range of terrains – and ride the way you want!
- Adjustable chain stabilizer prevents chain slapping and drops
- Switch stabilizer ON/OFF to match the terrain
- Gravel-tuned clutch tension
- Silent and uninterrupted rear shifting on rough terrain
- Total capacity: 42T
- Smooth and reliable mixed surface shifting
- Compatible with current road DUAL CONTROL LEVER
- Maximum front difference: 17T
- Top sprocket: Max. 11T/Min. 11T
- Low sprocket: Max. 34T/Min. 30T
Occasionally, without notice, manufacturers change product design and/or specifications.
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Delivery & Guarantee
UK Delivery Information
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