B'twin Rockrider 27.5" ST 120 Alloy Hardtail Mountain Bike

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B'twin Rockrider 27.5″ ST 120 Alloy Hardtail Mountain Bike

The B'TWIN Rockrider 27.5" ST 120 Mountain Bike features an aluminium hardtail frame with front suspension, 9 speed disc groupset (1 x 9), 27.5" wheels, weighing 15.1kg and is finished in black & blue.

B'Twin Rockrider 27.5" ST 120 HT MTB

  • B'TWIN Men's Alloy Hardtail MTB Frame with Front Suspension
  • 27.5" Disc Brake Wheels
  • 9 Speed (1 x 9)
  • Available in S, M & L in Black & Blue.
  • Weighs 15.1kg

The Rockrider ST 120 - good value entry level biking?

The ST 120 is the second model up in the Rockrider ST series, costing slightly more than the popular Rockrider ST 100. So what differentiates the ST 120 from it's cheaper sibling?

On first glance the obvious upgrade is disc brakes. Tektro's TKD 68 provide superior stopping power, and despite their mechanical (cable based) nature will offer better performance than V Brakes. These can easily be upgraded to a hydraulic system at a later date if you so wish.

The second difference is the single chainring setup, complete with 9 speed cassette. This will help reduce overall bike weight due to the absence of a front mech, shifter and two chainrings compared to a triple setup. As per many lower end bikes, Microshift provide the majority of the drivetrain, with the exception of a 9 speed KMC chain.

The ST 120 comes with an 80mm suspension fork and 27.5" wheelset, both of which will be reasonably heavy; however given the cost we can't complain.

Please note: it will be worth upgrading the handlebar from the stock narrow 640mm steel component to a wider alloy set; the bike will be more fun to ride and weigh slightly less.

In terms of weight, the Rockrider ST 120 Mountain Bike weighs approximately 250g / 1/2 lb less than the cheaper ST100 model, with measurements ranging from 15.1kg (S) to 15.5kg (XL).

So is it worth buying? In our opinion yes; it's a cost effective beginners mountain bike which can easily be upgraded as your skills progress.

This 27.5" mountain bike is designed for getting started with MTB touring in dry weather, for rides up to 1.5 hours.

An efficient, easy-to-handle MTB! Riding the ST 120 MTB you will feel the precision and light weight provided by the single chainring (1x9 speeds) and mechanical disc brakes.

Change speeds easily! Cycling comfort: Enjoy touring: raised position, 80 mm suspension, hammock saddle, FLEX seat post.

Ease of use: Adjust your speed without thinking: 9-speed single-chainring drivetrain.

Directional control: Control your trajectory: cable disc brakes, tyres with side knobs.

Efficiency: Pedal efficiently: light aluminium frame, 9 speeds and fast tyres.

Robustness: An ultra-strong MTB: welded saddle, double-wall rims.

The 100% aluminium CGF frame (Comfort Geometry Frame) is both comfortable and easy to handle. The slope angle has been designed to keep your back straight, while the rear bases were shortened to make the bike very agile in turns.

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 (55 kg to 105 kg) 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: A SINGLE CHAINRING LIKE THE PROS!: The single chainring is easy and efficient to use:.

1 chainring and 9 speeds. Accelerate on the flats and easily tackle the climbs. With a single lever on the handlebar, you can change gears while hardly thinking! ROCKRIDER FC ATB 100 - 32-tooth single chainring equipped with 2 chain guides (anti-derailment).

MICROSHIFT RD-M46-L rear derailleur. MICROSHIFT SL-759 right shifter. MICROSHIFT H092 9-cog cassette (11-36 teeth).

Wide, sturdy KMC Z9 chain HANDLEBARS, STEM, GRIPS: With a stem that tilts 10 degrees upwards, the riding position of the ST 120 is raised, accessible, and comfortable. In detail:. 90mm aluminium stem with an angle of 10 degrees for maximum comfort.

640mm wide steel handlebar for stability and control. "Soft touch" lamellar grips for a firm yet soft and pleasant grasp.

Saddle: The saddle of the ST 120 is welded to prevent any movement of the saddle.

And because your comfort is our priority after your 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 (350mm or 400mm long depending on the bike size). Its smaller 27.2mm diameter provides your seat with natural flexibility, 30% more than a standard solution.

MECHANICAL DISC BRAKES: The Tektro TKD 68 160 mm double disc brakes provide powerful, progressive braking at the front and rear. The aluminium Tektro brake levers are precise, and easy to hold. The brakes can be applied using only two fingers.

3 or 4 sets of 10 dry, intermittent stops are enough to break in your pads. 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 120 are tolerant and sturdy, with 19 mm double-walled rims with 28 spokes.

Start overcoming obstacles fearlessly, including small rocks, cracks, holes and bumps! Because your first rides will be on dry ground, the Dry 27.5 x 2.0 tyres are most suitable. The central section has low rolling resistance (faster), while the side lugs provide good grip on turns.

Platform pedals: The Rockrider ST 120 mountain bike comes with resin mountain bike platform pedals for lower weight and increased safety.

If your foot can slip off the pedal, you're less likely to injure yourself.

TRANSPORT & STORAGE: We added a quick release system for easily removing/reattaching the front wheel.

Accessories: The ST 120 mountain bike comes with a bell, lights, wheel reflectors, and pedals.

Weight: S - 150-164cm : 15.1 kg.m - 165-174cm : 15.2 kg.

L - 175-184cm : 15.3 kg.

XL - 185-200cm : 15.5 kg.

.. more details.

Rockrider 27.5" ST 120 Mountain Bike Specification

Bike TypeMountain Bikes
Weight15.1kg
Frame MaterialAlloy
Frame TypeHardtail
Fork TypeSuspension Fork
Brakes TypeDisc Brakes
Number of Gears9 Speed
ChainringsSingle Chainring
Cassette9 Speed
Wheel Diameter27.5"
ColourBlack & Blue
SizeS, M & L
GenderMen's
Designed forMTB
BrandB'TWIN
RetailerDecathlon
RRP£299.99
Lowest Price£299.99

Men's Hardtail Mountain Bike Deals

How about some of these Men's Hardtail MTB deals instead?!

Or check out all of my latest mountain bikes deals.

Not convinced this is the right MTB for you? Check out my Mountain Bike page, full of my latest sale bikes - from 26" Alloy Hardtails to 29" Carbon Full Suspension Bikes, and everything inbetween - all searchable by size. Or for those of you who prefer tarmac, view my road bikes listings instead.

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