29" Full-Suspencion Carbon Mountain Bike - Red/Black


This 27.5" mountain bike has been designed and developed to best suit mountain bike rides lasting two to three hours, all year round, in any conditions.

Boost your performance with the new full-suspension carbon/aluminum 29" frame. Get your best times to the finish line during marathons and long-distance races thanks to the 120mm suspension.

Size: size guide


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Product benefits



Win: 12-speed SRAM GX Eagle, Mavic Crossmax (29") Tubeless Ready wheels.



Give it your all: full suspension carbon frame, alu rear (frame: 2.2 kg in S)

Shock absorption

Shock absorption

Fork: 120mm Rockshox Reba RL, 120mm Combo Lock 2 Radium Metric shock.

Braking power

Braking power

Experience the power of the SRAM Level T double-piston brakes.

Technical information


Entirely designed and developed in France at the B'Twin Village (Lille).
The Rockrider team designed and tested this XC 900 S 29" mountain bike with the involvement of XC mountain bikers like our technical partner and professional mountain bike racer: Milton Ramos, winner of many XCM races around the world.

To better satisfy your needs, we assembled the Rockrider XC 900 S 29" at our own factory in Lille, just steps away from the bike design team.


Men's or women's mountain bike? This Rockrider XC 900 S 29" is unisex.

For greater comfort, women can replace the saddle with the 500 Women's Sport saddle that is adapted to women's bodies.


Several sizes available:
S: between 1.55 m and 1.64 m
M: between 1.65 m and 1.74 m
L: between 1.75 m and 1.84 m
XL: between 1.85 m and 1.95 m

If you are on the edge between 2 sizes, we recommend following the exact size listed.


New FS Rockrider Cross Country 29" carbon frame.
ALU 6061/6013 rear triangle
Carbon rod
Specific geometry for 29" wheels
148mm x 12mm rear axle. BOOST
"Press fit 92" bottom bracket
31.6 mm diameter saddle tube and internal guidance to fit the telescoping seat post
Access hatch for easy bottom bracket maintenance
Compatible with 1 bottle cage.
Single chainring only
Weight in size S: 2.2 kg
Aluminium axles (light weight)

Front suspension

Make obstacles disappear.

Rockshox REBA RL front suspension with 120mm of travel.
BOOST axle.
Direct lockout front suspension (3 positions) on the handlebars with the Combolock 2 grip.
3 modes: locked, medium, and open

ComboLock 2

This ROCKRIDER XC 900 S mountain bike is equipped with the new Combolock system: better ergonomics and easier to use. The contact surface is larger and integrates better with the grips.
A new smaller action angle for greater accuracy.


Manitou Radium Expert Metric shock
Specific setting for XC 900 S
120mm travel, 190x45mm
3 lockout adjustment positions (compression damper)
Adjustable bounce


SRAM GX Eagle drivetrain, single 1x12 chainwheel, for larger metres of development and climbing more easily.
Rack: SRAM Turativ Stylo 34 teeth to pick up more speed. SRAM XG1275 Eagle cassette with 12 cogs: 10/50 teeth.The 50-tooth cog ensures you get the right gear ratio for climbing the most challenging sections, while the 10-tooth cog is ideal for achieving maximum speed.

Handlebar / Stem / Steering / Grips

Keep stable and find your attack position.

Comp Flat Rockrider handlebars, 720mm wide for improved control of the 29" wheels
Rockrider Comp stem designed according to bike size (70mm in size M, 80mm in size L and 90mm in size XL).
Semi-integrated headset with sealed bearings.
New ROCKRIDER 900 Combolock grips for better integration. The Combolock lockout is lighter, and the "lock on" function has been added (attaches to the handlebars with a screw system).


The XC 900 mountain bike S is equipped with a 31.6 mm diameter seat post. The 400 mm length (350 mm in size S) allows a wide range of adjustment.

The new Rockrider XC / AM saddle with Ergofit system provides comfort as you pedal. A reinforced area has been added (Cordura).
The saddle weighs 265g.


The choice of double hydraulic disc brakes for incisive braking.
SRAM Level T hydraulic disc brakes.
180 mm front disc, 160 mm rear disc.


29" : Wheels up to the challenge of XC!

Mavic Crossmax Tubeless Ready wheels in 15 mm at the front and 12 mm at the rear. BOOST
Inner rim width: 25 mm.Tubeless Mavic rim strip.
UST valve included.
XD Pound Wheel
ETRTO Dimension: 622x25TSS
Sealed bearings.
Weight of both wheels without tyres: 1,930 kg


Hutchinson Kraken Tubeless Ready 29x2.3 tyres
Tyre with a versatile profile for performance on all types of terrain.


This Rockrider XC900S MTB is fitted with our exclusive cyclometer mount:
This mount is compatible with Garmin or Sigma cyclometers/GPS which don't require additional fittings for your headset.


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).


The front and rear wheels attach and remove in 1 motion: you just need a hex key (size 6).
The rear derailleur has a screed that locks and unlocks easily to easily attach or remove the rear wheel.


11.9kg in size S, without pedals. 12 kg in size M, without pedals.12.1 kg in size L, without pedals.
12.2 kg in size XL, without pedals.
Weight with tubeless ready tyres.

Weight can vary based on the tolerance of the components.
The complete bike + fully equipped rider should not exceed 120kg


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.
Check out all our tips on handling your bike:


The frame and peripherals are guaranteed for life. Availability of spare parts: 2 years

Product concept & technology

Product Composition

Frame 50% Aluminium 6061, 50% Carbon Fiber


We recommend storing your mountain bike in a cool, dry place, away from corrosive products and salty air.


Please visit your local Decathlon store for any pre-purchase tests.

Approved By

Milton Ramos, professional cross country mountain biker on the most demanding routes in the world, including the Iron Bike, Andalucia Bike Race, Hero Himalaya...

Maintenance advice

Rinse in clean water after use.


To have more informations about this product, consult the notice


29" Full-Suspencion Carbon Mountain Bike - Red/Black
29" Full-Suspencion Carbon Mountain Bike - Red/Black
29" Full-Suspencion Carbon Mountain Bike - Red/Black
29" Full-Suspencion Carbon Mountain Bike - Red/Black
29" Full-Suspencion Carbon Mountain Bike - Red/Black
29" Full-Suspencion Carbon Mountain Bike - Red/Black
29" Full-Suspencion Carbon Mountain Bike - Red/Black
29" Full-Suspencion Carbon Mountain Bike - Red/Black
29" Full-Suspencion Carbon Mountain Bike - Red/Black
29" Full-Suspencion Carbon Mountain Bike - Red/Black
29" Full-Suspencion Carbon Mountain Bike - Red/Black



Q:How to assemble your bike?

A: Everything you need to know about making sure your bike is comfortable, secure and ready to ride.

Q:Do you offer a Cycle To Work scheme?

A: Find out everything you need to know about way of getting to work that’s for good you and the environment. Check Here
Products sold and shipped by Partners are not eligible for Cycle to work Schemes

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