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ROCKRIDER XC 900 Carbon Hardtail Mountain Bike - 27.5"

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was £1,499.99 -20%


This price includes a recycling fee for electrical equipment and batteries DecathlonDeeeTaxMentionAfterPrice / Since

From 06/02/2020 To

* Sales from to Until end of stock
* From 06/02/2020 and limited stock
£1,499.99 -%
This price includes a recycling fee for electrical equipment and batteries DecathlonDeeeTaxMentionAfterPrice / Since

* From To

* Sales from to Until end of stock
* From and limited stock
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Designed for regular training and getting into Cross Country (XC) competitions. Push yourself and measure yourself against others. Give it your all with the XC 900 hardtail mountain bike with a stiff and responsive carbon frame. This race ready machine is ready to get you to the finish line faster than every before thanks to the the Rockshox Reba RL 100mm forks, Mavic Crossmax wheels and SRAM GX Eagle 1x12 drivetrain.
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Due to high demand, we are currently suspending online delivery for bikes. We are now increasing the availability of our bikes in our store showrooms while continuing with our Click and Collect service. This is a temporary measure and we thank you for your patience and understanding.

Product benefits

Efficiency Win: 12-speed SRAM GX Eagle, Mavic Crossmax (27.5") Tubeless Ready wheels
Lightweight Give it your all: full carbon frame and seat post (frame: 1.1kg in M)
Shock absorption Overcome obstacles with the Rockshox Reba RL 100mm self-locking fork.
Braking power Enjoy powerful SRAM Level T dual-piston brakes with 160mm discs.

Technical Information


Entirely designed and developed in France at the B'Twin Village (Lille), this mountain bike is the fruit of the work of an expert team of passionate cross-country mountain bikers. The Rockrider team has designed and tested this XC 900 mountain bike, involving XC mountain bikers at every stage of the projectTo ensure you are completely satisfied, the XC 900 is assembled in our own factory in Lille, metres from our development team.

A unisex mountain bike

Men's or women's mountain bike? The Rockrider XC 900 is for men and women.
For greater comfort, the women on our mountain bike team recommend replacing the saddle with the Women's 500 Sport saddle, which is adapted to women's bodies.


Several sizes available:
M: between 1.60m and 1.74m
L: between 1.75m and 1.84m
XL: between 1.85 m and 1.95 m
If you are on the limit between 2 sizes, we recommend following the exact size listed.


This Rockrider Cross Country frame is completely made from carbon. We have optimised the carbon fibres to improve the rigidity and lightness of the mountain bike.
The frame is handmade.
ESR-compatible (Electronic Shifting Ready) frame with special pass-throughs for electronic cables.
Rear axle 142mm x 12mm.
"Press fit 92" bottom bracket.
27.2mm diameter seat post.
Compatible with 1 bottle cage.
Weight in size M: 1.1kg.

Front Suspension

Obstacles no longer pose a problem.
ROCKSHOX REBA RL front suspension with 100mm of travel.
Direct locking front suspension (in open or closed position) on the handlebar using the COMBO LOCK handle.


This mountain bike has no rear suspension.


Go anywhere, uphill or downhill, with this 12-speed cassette.
SRAM GX Eagle drive train, 1x12 single chainring, for easier pedalling and climbing.
Rack: SRAM Turativ Stylo - 34-tooth for achieving greater speed.
SRAM XG1275 Eagle cassette with 12 cogs: 10/50 teeth.The 50-tooth cog ensures good gear ratio for climbing more challenging sections, whilst the 10-tooth cog is ideal for maximum speed.


Keep stable and find your attack position.
680mm wide Rockrider Comp Flat handlebars.
The B'TWIN COMP stem is adapted to the size (70mm in size S, 80mm in size M, 90mm in size L, and 100mm in size XL).
Semi-integrated headset with sealed bearings.
Lightweight, "lock on" style Rockrider 900 grips screw onto the handlebars.

Saddle / Seat post

For maximum lightness and comfort, the XC 900 is equipped with a 27.2mm diameter B'Twin Carbon seat post. The 400mm length allows a wide range of adjustment.
The Rockrider XC/AM saddle provides comfort as you pedal.
The saddle weighs 265g.


The choice of double hydraulic disc brakes allows precise braking.
Exclusive SRAM Level T hydraulic disc brakes.
Front 160mm disc, 160mm rear disc.


27.5" : wheels up to the challenge of XC!
Mavic Crossmax Tubeless Ready wheels, 15mm at the front and 12mm at the rear. Inner rim width: 22mm.Tubeless Mavic rim strip.UST valve included.Sealed bearings.
Weight of both wheels without tyres:1.735kg


Grip and move over all types of terrain.
Hutchinson Cobra 27.5x2.1 Air Light tyres.
Light, high-performance tyres with a low profile, designed for stony, varied terrain.
Lugs to optimise traction
High side lugs to optimise grip on turns.


The bike is supplied with B'Twin Flat Pro platform pedals. However, for better performance when pedalling, we recommend replacing them with clipless platform pedals (not included).

Easily transport and store your mountain bike

The front and rear wheels can be mounted or removed in one easy step: you just need a hex key (size 6).
The rear derailleur has a pin that easily locks and unlocks to mount or remove the rear wheel.


10.4 kg in size M, without pedals.
10.6 kg in size L, without pedals.
10.8 kg in size XL, without pedals.
The weight can vary based on the tolerance of the components.
The complete bike (MTB + fully equipped rider) should not exceed 120kg.

Our advice for your first ride

During your first outings, the equipment on your bike will gradually adjust itself (chain, dérailleur, brakes, etc.).We offer a free inspection in the 6 months following purchase, where our technicians will carry out a 13-point check of your bike. Access all our advice on handling your bike:


10.4 kg

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Composition / advice

100.00% Carbon Fiber
Stock advice We recommend storing your mountain bike in a cool, dry place, away from corrosive products and salty air.
instructions To get more information about this product, please read instructions

Our commitments

Test Product Please visit your local Decathlon store for any pre-purchase tests.
Guarantee : Frame 5 years.Details on our website. Availability of spare parts: 2 years


Q : How to assemble your bike?
Everything you need to know about making sure your bike is comfortable, secure and ready to ride.
Q : How do you adjust your brakes?
Having properly functioning brakes is vital when out on the road. Check out how to get them working to your liking.
Q : How to replace a brake lever on a bike?
Having properly functioning brakes is vital when out on the road. Here’s a video to show you how to make sure your new brake level is working nicely.
Q : How to replace a disc brake?
Having issues with your disc brake? Then this video is for you.
Q : How to adjust your bike handlebar?
A suitable handlebar height is essential to your cycling safety and comfort. Find out how to adjust it to your liking with our video.
Q : Do you offer a Cycle To Work scheme?
Find out everything you need to know about way of getting to work that’s good you and the environment.Check Here

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XC 900 Carbon Hardtail Mountain Bike - 27.5
Maintenance and repair
Maintenance and repair
XC 900 Carbon Hardtail Mountain Bike - 27.5"
Because you look after your own health, we look after that of your products: tips for initial settings, maintenance and repair advice, video tutorials, FAQs, instructions...
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