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MEN SPORT TRAIL MTB BIKE

ROCKRIDER St 520 Mountain Bike, Black - 27.5"

ROCKRIDER
4/5

Colour : BLACK

User rating
Decathlon
was £279.99 -%

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£279.99**
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£279.99 -%
Before£0.00NoW£279.99**
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* From and limited stock
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This 27.5" MTB is designed for MTB rides lasting 2 to 3 hours, all year round. Go faster while controlling your trajectory. The mechanical disc brakes on the ST 520 MTB allow you to confidently take on descents, winding trails, and obstacles.
Not Available Now

We currently have limited capacity to build bikes in our warehouse. Due to this, we are limiting the number of bikes we sell per day and you might not be able to process your order at checkout. The count resets at 11pm every day so that would be the best time to try, although we do have a peak of attempts at this time so we can't guarantee a slot for everyone.

Technical Information

WHAT SIZE MOUNTAIN BIKE TO CHOOSE?

Several sizes available:
S: between 1.50m and 1.64m
M: between 1.65m and 1.74m
L: between 1.75m and 1.84m
XL: between 1.85m and 2.00m
To adapt the bike to your height and size, try these tips:
1/ Sitting on the saddle, you should be able to touch the ground with the tips of your toes.
2/ To adjust the seat height, your knee should be slightly flexed with your foot on the pedal in the lowest position.
3/ If you're between two sizes, choose the larger size.

UNISEX FRAME

With a heavily sloped top tube and a wide range of sizes (from S: 1.50 m to XL: 2.00 m).
The ST 520 mountain bike frame is UNISEX.
The ST 520 mountain bike is available with the same frame in a WOMEN'S version: fitted seat, narrower handlebar, shorter stem, fork with a more flexible spring, and brake levers that are closer together.
As a WOMAN, if you choose the MEN'S model, we recommend at least purchasing the WOMEN'S SPORT 500 saddle which is fitted to the female form.

A WORD FROM THE TEAM

The ST 520 mountain bike was fully designed and developed by our passionate MTB team at the B'Twin Village in France (Lille).
Mountain bikers we talked to expressed their need for control so they can take more risks and continue to improve their technical skills. With that as a starting point, we designed and tested the ST 520 mountain bike, involving MTB riders at every stage.

A LIGHT, COMFORTABLE FRAME

Our designers created a frame that's easy to get onto.
The CGF frame (Comfort Geometry Frame) EVO is made of 100% aluminium for greater comfort. Its slope was carefully designed to keep your back straighter.

FRONT SUSPENSION

The 80 mm front suspension helps you get started with overcoming obstacles on slightly uneven trails easily.
Easily adjust the hardness using U-Fit technology (weight adjuster). Simply set the number to your weight using the dial on the fork.

REAR SUSPENSION: NONE

This mountain bike has no rear suspension.
It is a "semi-stiff" mountain bike: perfect for beginners launching themselves into their first mountain bike touring rides.
Compared to a full suspension mountain bike (with rear suspension), the advantages are clear: the mountain bike is lighter; you spend less energy on flat ground.

DERAILLEUR & DRIVETRAIN:

3 x 8 speeds, 24 speeds total!
2 shifters on the handlebar.
Left (chainrings): control ascents/descents.
Right (speeds): more precise control over your pedalling.
In detail:
-ROCKRIDER FC ATB 500 triple chainring - 22/32/42 teeth
-SHIMANO ALTUS front derailleur
-MICROSHIFT RD-M46-L rear derailleur
-MICROSHIFT TS39 shifters
-SHIMANO 8-speed cassette (11-32 teeth)
-KMC Z7 wide and sturdy chain

HANDLEBARS, STEM, GRIPS

The adjustable stem brings the ST 520 controls to your hands. The all-aluminium ROCKRIDER stem is 70 mm (size S), 80 mm (size M/L), or 90 mm (size XL) and can be raised to 5 adjustment intervals: + 0mm, + 7.5mm, + 15mm, + 22.5mm, + 30mm.
In detail:
- 680mm oversize ROCKRIDER SPORT aluminium handlebar
- ROCKRIDER SPORT "soft touch" ergonomic grips for good grip and a comfortable feel.

SADDLE

The ST 520's saddle fixing (welded) prevents any saddle movement as you cycle.
Because your comfort is our next priority after safety, we've added an exclusive wider Ergofit saddle with a hammock shape.
Easily adjust the height of your saddle with the Flex steel seat post, either 350mm or 400mm long (according to the bike size). Its reduced diameter of 27.2mm provides your seat with natural flexibility, 30% more than a standard solution.

MECHANICAL DISC BRAKES

The Tektro TKD 68 double disc brakes provide powerful, progressive braking at the front and rear. The aluminium Tektro brake levers are light, precise, and easy to hold. The brakes can be applied using only two fingers.
We recommend that you have your brakes checked at least once a year.

27.5" WHEELS & TYRES FOR DRY TERRAIN

The 27.5" wheels of the ST 520 are tolerant and sturdy, with 19 mm double-walled rims with 28 spokes. Overcome your first obstacles without fear: small rocks, cracks, holes and bumps!
Because your first tours will be on dry ground, the Dry 27.5 x 2.0 tyres are most suitable. Their performance is optimised thanks to the rounded central section, whilst the side lugs provide good grip on turns.

PLATFORM PEDALS

The Rockrider ST 520 mountain bike comes with flat mountain bike pedals made from hard resin for lighter weight and greater safety.
If your feet can slide off the pedals when needed, there's less risk of injury.
The pedals on the ST 520 are compatible with toe clips.

TRANSPORT & STORAGE

We added a quick release system for easily removing/reattaching the front wheel.
Tip: a bike rack is an easy way to transport your mountain bike without dirtying your car.

ACCESSORIES

Your ST 520 mountain bike is supplied with a bell, lights, wheel reflectors and pedals.
The frame is compatible with:
- Front and rear mudguards
- Stand
- Bottle cage
- Saddle bag
- Rear pannier rack
- Child seat
etc.

COMFORT & SAFETY

Your bike's fittings (chain, derailleur, brakes, etc.) will adjust over time. Take advantage of a free servicing within 6 months after purchase. Our technicians will carry out a 13-point check of your bike. Just come to your nearest Decathlon workshop with your Decathlon card and/or receipt.

LEGAL DISCLAIMER

To ensure components last longer, we recommend a maximum load of 120 kg (rider and MTB included).

Weight

S - 150-164cm: 14.35 kg
M - 165-174cm: 14.45 kg
L - 175-184cm: 14.55 kg
XL - 185-200cm: 14.7 kg
Weight without pedals.

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Composition / advice

Composition
Frame
100.00% Aluminium
Stock advice After washing, rub with a dry cloth to remove all traces of moisture. Store your mountain bike in a cool, dry place, away from corrosive products and salty air.
Restricted use : Not suitable for XC, All Mountain, Enduro and BMX.
Legal notice To ensure components last longer, we recommend a maximum load of 120 kg (rider and MTB included).
How to maintain and repair your product

Our commitments

Test Product Our engineers always have real riders test all our products in real conditions. These tests round out our lab tests and let us validate all our products before they hit store shelves.
Guarantee : Lifetime (frame, stem, handlebars). Availability of spare parts: 2 years.

Product benefits

Cycling comfort Enjoy touring: raised position, 80 mm suspension, hammock saddle, FLEX seat post
Directional control Control your trajectory: mechanical disc brakes, tyres with side knobs.
Efficiency Smooth riding: light aluminium frame, 24 speeds and fast rolling tyres.
Durability An ultra-strong MTB: welded saddle, double-wall rims.
Lifetime warranty ROCKRIDER offers a lifetime warranty on the frame, handlebars and stem.

FAQ

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

Your reviews

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FAQ

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

Our services

St 520 Mountain Bike, Black - 27.5
Maintenance and repair
Maintenance and repair
St 520 Mountain Bike, Black - 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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