Made for All new 27.5" MTB fully designed and exclusively produced by b'Twin. This great value 650b hardtail MTB with a lifetime warranty.
This all new Rockrider 540 model is packed with so many great features and market leading specification: 100mm hydraulic​ forks with lockout, 27 speed SHIMANO Altus gears, HAYES Radar hydraulic discs.
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Cycling comfortMore fluid 100 mm hydraulic fork. Ergonomic saddle. Height-adjustable stem.
EfficiencyShimano Altus 27 speeds. Lightweight, fast rolling tyres. Fork with lockout.
PrecisionHydraulic disc brakes.Tyres made of soft rubber. Wide pedals with a strong grip.
Ease of useLockout your fork in a single step. Ergonomic built-in seat clamp.
Lifetime warrantyB’Twin provides a lifetime warranty on the frame, stem and handlebar.
Warrantylifetime warranty​ on the frame, stem and handle bars.
Technical Information

B'Twin Flat Evo VP resin pedals: both sturdy and lightweight. A large pressure surface area for more power while pedalling and better steering of your mountain bike. More aggressive pins for better contact between the foot and the pedal.
Exclusive B'Twin Upside Down 0/30 stem in aluminium for less weight. 80 mm (size M) and 90 mm (size L or XL): shorter provides more precise steering. Can be raised by up to 3 cm with 5 adjustment positions (+0 mm, + 7.5 mm, + 15 mm, + 22.5 mm and + 30 mm). Is 15% stiffer thanks to its width being increased by 48%, providing more precise steering.
Hayes Radar hydraulic disc brakes on front and rear: more powerful and progressive braking even in rain and muddy conditions, with only minimal pressure on the levers required.
Suntour XOR 100 fork with 100 mm travel. Fork stiffness can be adjusted (more/less). Fork lockout to prevent bobbing on faster terrain.
Prowheel Flint 401 triple-chainring chainset (22/32/44 teeth). Shimano Altus 9-speed rear derailleur. Microshift front derailleur. Shimano Altus M370 shifters with speed indicators. Shimano cassette with 9 cogs and 11-34 teeth.
14.1 kg in size M without pedals
B'Twin Sport handlebar in aluminium for less weight. 660 mm (size M) and 680 mm (size L or XL): wider for extra stability. Oversize diameter for added stiffness.
Rockrider CGF Evo (Comfort Geometry Frame) in 6061 aluminium. For 27.5" wheels with a comfortable position thanks to a raised steering centre. Seat is 5 times more flexible than a standard frame thanks to a narrow 27.2 mm seat post. Low crankset: Mountain bike keeps stable in turns and easy to place one's foot on the ground thanks to an open steering angle (69.5°): keeps mountain bike stable while riding. Short rear wheel base: bike is easy to turn.
Exclusive B'Twin All Terrain Dry 27.5" x 2.0 tyres. A system of lugs specially designed for all-terrain use on any type of surface. Lighter tyre sidewalls to reduce the effect of rotating mass. Includes a pressure guideline chart based on rider weight.
B'Twin Sport seat post in aluminium for less weight. 27.2 mm diameter provides the seat with a natural flex that's 5 times greater than that of a classic seat post. 400 mm long, offering a wide adjustment range.
Exclusive Sport 500 saddle offers exceptional comfort thanks to its wider "hammock" shape and wide distribution of the pressure points regardless of width of the rider's pelvis.
Semi-integrated Aheadset offers improved watertightness, more precise steering, and an integrated look. B'Twin Sport handles with grooves, 120 mm long: true riding comfort.
1) The components seen on the bicycle in the videos may change from the actual product. 2) The bicycle will be delivered in 95% assembled condition(Handlebar and pedals have to be assembled). The directions for the cycle assembly will be sent via mail ( if you have subscribed) and available on the product pages. The tools for assembly are provided with the cycle only for online buyers.
1) If you will need a spare part to be replaced, we have it all at our workshop. You will have to drop by our workshop to get your cycle serviced. 2)The 3-month, free checkup is valid only if the user is able to take the bicycle to a decathlon workshop. 3) All bicycle accessories need to be purchased separately.
Information / Concept / Technology
Stockage tips
Please store the cycle in a cool and dry place away weathering agents like the sun and rain. Always keep the tyres inflated.



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It is the best cycle , you buy
Used for 7 to 12 months
Buy it
front derailleur touching chain again.
Used for 3 to 6 months
ibought 3 months ago since that time i have been facing the issue usually i ride sometimes. before the gear shifting issue in front crank when ever i change the gear in front it was not working properly. then i took it to workshop till now the issue is solved, but still the front derailleur is touching the chain. i told to change because its from manufacture defect but they are charging for it feel sad.
Response of the brand

Thank you for taking the time to give us your review. Apologies for the bad experience. Please let us know from which store you have purchased the bike from and we will get in touch with you regarding the problem. We do a 14 point check before selling the bike in which the front derailleur issue would have been noticed. 

I remain available at your disposal.  

kpg not found this answer helpful
Mind blowing bicycle
Used for 2 to 8 weeks
It's a excellent MTB with a very competitive price. Suspension is superb and brakes are too good .....Gear shifts very smoothly I really love this bike.
Pathetic cycle
Used for 3 to 6 months
I bought this cycle 2 months ago ... Chain got rusted and the seat is not setting up on one place and coming down I think the seat lock is also damaged.. pathetic product...
Response of the brand
Hi Farhaan, 

Thanks for your feedback. We regret the negative experiences you have had with your bicycle. Bicycle chains are prone to rust if stored or used in a moist or wet climate. Steel components of chains can withstand corrosion if applied with lubricants on a regular basis. In regard to seat clamp  

A grt product and well tested worldwide.Enjoying
Used for 2 to 8 weeks
Replaced it with my old cycle and can definitely feel the difference .. want some accessories but feel it little costly so still waiting
Really rocking
Used for 2 to 8 weeks
Hi I’m using this bicycle for last 7/8 week and really it is superb in riding with city road and off-road ,great controls and smooth shifting gear. Graphics of this bicycle is really attractive.
B-twin bst buddy to have in life
Used for 1 week or less
Was my wish list to buy one ,today I own a b-twin 540 and I am happy the best cycle I have rode till present excellent design and shifting gears .I can proudly say a good investment
Best store ever
It is best sports shop ever
Good product ****
Used for 2 to 8 weeks
RR 540 is a good cycle
Take it anywhere or everywhere.
Used for 3 to 6 months
I am using this bike for around five and a half month now. Commuting to office daily. That's around 25 kms daily. The roads are extremely bad and most of the times ride on the footpath which is mostly of gravels and uneven concrete chunks. It has an amazing grip and the brakes are super awesome combined with the front suspension. Only thing that's not so great is the seat. It gets really uncomfortable at times. It can be fixed with a proper memory foam seat cover and proper calibration of the seat.
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