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Easy and effective: single chainring, disc brakes

  • 15 - Cycling - Men's 27.5
Reference : 8529703
15 - Cycling

B'TWIN Men's 27.5" Mountain Bike ST 100 - Black/Blue

B'TWIN
Our team has designed this 27.5" MTB (26" in size XS) with a single chainring and disc brakes for your first rides of up to 1.5 hours in dry weather. Easy and effective! With the ST 120's single chainring controls and disc brakes, you'll feel light and precise!

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TECHNICAL INFORMATION

WHAT OUR TEAM HAS TO SAY

We created this ST 120 mountain bike at our B'Twin Village (Lille, France) especially for mountain biking enthusiasts.
Recreational mountain bikers told us they wanted comfort, effectiveness and durability. Those features were our starting point as we designed, developed and tested the ST 120 mountain bike, with real riders involved throughout the project.

A UNISEX MOUNTAIN BIKE

The ST 120 mountain bike is designed for men and women alike.
The ST 120's CGF frame has been designed in great detail to make it light and comfortable, with a very pronounced top tube slope, and a very broad range of sizes (from XS: 1.45 m to XL: 2.00 m).
To make the most of the improved comfort, the women of the Rockrider team recommend the 500 Women's Sports saddle, which is adapted to the female figure.

HOW TO CHOOSE THE SIZE OF YOUR ST 120 MOUNTAIN BIKE

Several sizes available:
XS: between 1.40m and 1.54m
S: between 1.55m 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 saddle height, your knee should be slightly flexed with the foot on the pedal in the lowest position.
3/ If you're between two sizes, choose the larger size.

A light, comfortable, fun frame

Our designers have created an entirely new frame that's easy to get onto for both men and women.
The CGF frame (Comfort Geometry Frame) is 100% aluminium for optimal comfort and excellent manoeuvrability. The slope angle has been designed to keep your back straight whilst the low rear ensures the bike is very agile when turning.

FRONT SUSPENSION FOR CUSHIONING LUMPS AND BUMPS

The Suntour XCT 80mm front suspension is designed for slightly uneven trails and helps you overcome your first obstacles with no worries.
It features U-Fit (weight adjuster) technology so that you can adjust the stiffness according to the rider's weight using a dial.

REAR SUSPENSION: NONE

This mountain bike has no rear suspension. It is a "semi-stiff" mountain bike: ideal for beginners.
Compared with a full suspension bike (with rear suspension) the benefit is clear: it weighs much less so you waste less energy on flat terrain.
A "semi-rigid" bike such as the ST 120 is a good choice for your first rides!

DERAILLEUR & DRIVE TRAIN: the ease of a SINGLE CHAINRING

The single chainring is easy and efficient to use.
1 chainring and 9 speeds.
Accelerate on the flat and take on climbs with no compromise.
With a single lever on the handlebar, there's no need to even think!
-ROCKRIDER FC ATB 100 - 32-tooth single chainring equipped with 2 chain guides
-MICROSHIFT RD-M46-L rear derailleur
-MICROSHIFT SL-759 right shifter
-MICROSHIFT H092 9-cog 11 to 36 tooth cassette
-Wide, sturdy KMC Z9 chain

STEM, HANDLEBAR, GRIPS: FOR GOOD HAND POSITIONING

With a stem that tilts 10° upwards, the ST 120 gives you a raised, accessible, comfortable riding position.
In detail:
90mm aluminium stem with an angle of 10° for maximum comfort
- 640mm-wide steel handlebar, for stability and control
-"Soft touch" lamellar grips for a firm yet soft and pleasant grasp.

SADDLE: SIT COMFORTABLY!

The ST 120'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.

CABLE DISC BRAKES: GET A GRIP ON YOUR BRAKING

The Tektro TKD 68 or Hayes M-X5 160 mm cable double disc brakes provide powerful, progressive braking to the front and rear. Whilst the aluminium Tektro brake levers are light, precise, and easy to hold. Just two fingers are all you need to brake.
Try to get your brakes adjusted at least once a year.

27.5" wheels & tyres for dry terrain: READY TO ROLL?

Overcome your first obstacles without fear: small rocks, cracks, holes and bumps!
The wheels of the ST 120 are tolerant and robust, with 27.5" double-walled 28-spoke rims (26" for size XS).
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 fast central section, whilst the side knobs provide good grip on turns.

FLAT PEDALS

The Rockrider ST 120 mountain bike comes with flat mountain bike pedals made from hard resin for lighter weight and greater safety.
If your foot slides on the pedal, there's less risk of injury.

EASILY TRANSPORT AND STORE YOUR MOUNTAIN BIKE

Not all rides start on your doorstep. Need to take off the front wheel or transport it? To make it easier to mount / remove your front wheel, we've fitted it with a quick-release system.
A bike carrier will make your life easier if you want to avoid dirtying your car.

ACCESSORIES

Your ST 120 mountain bike is supplied with a bell, lights, wheel reflectors and pedals.
The frame is compatible with:
-Front and rear mudguards (Flash MTB or MTB 700)
-Stand (500 Adult Base)
-Bottle cage
-Saddle pouch
-Rear pannier rack
-Child seat (Polisport Groovy frame mounted)

COMFORT & SAFETY

We recommend that beginners wear cycling shorts with a pad (foam in the shape of a saddle) or a gel saddle cover to reduce soreness.
For longer rides, remember to take something to drink (e.g: a hydration bladder or bottle).
In all circumstances, even for a short ride, wearing a helmet is essential!

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COMPOSITION / ADVICE

Composition
Frame (for bike)
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, BMX.
instructions To get more information about this product, please read instructions
Legal notice Your bike's weight may vary due to tolerances in the components. To make your wheels last longer, we recommend not exceeding the maximum weight of 120kg (rider with mountain bike).

OUR COMMITMENTS

Test Product To increase the level of comfort, we also recommend that beginners wear cycling shorts with a protective pad and / or a gel saddle cover.
Guarantee : Lifetime (frame, stem, handlebars). Availability of spare parts: 2 years.
 

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