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B'TWIN Rockrider ST 920 Kids Alloy Mountain Bike - 24"

until £349.99 -%


This price includes a recycling fee for electrical equipment and batteries DecathlonDeeeTaxMentionAfterPrice / Since

From To

* Sales from to Until end of stock
* From and limited stock
£349.99 -%
This price includes a recycling fee for electrical equipment and batteries DecathlonDeeeTaxMentionAfterPrice / Since

* From To

* Sales from to Until end of stock
* From and limited stock
Check availability in store
We've designed this mountain bike for kids aged 9 to 12 years (135 to 150cm) wishing to perfect their MTB techniques. Equipped with the same aluminium frame as the 24" ST 900, this mountain bike has an air suspension fork to adjust to the child's weight and hydraulic disc brakes for effective downhill braking
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. If you are unable to process your order at checkout, please return the following day to make your purchase.


Product benefits

Ease of use ALU frame and chainset for less weight.
Quick release for removing the wheels.
Brake control Front/rear hydraulic disc brakes: powerful, progressive braking
Efficiency Air suspension fork, Skinwall tyres for less weight, 9 speeds
Cycling comfort Sports saddle combined with an aluminium seat post for greater comfort

Technical Information

A frame that is suitable for mountain biking.

Our engineers have designed a new aluminium frame. Durable, lightweight and responsive: designed for tackling any obstacles when out mountain biking.

Don't be scared of riding downhill!

Powerful, progressive braking thanks to the front and rear hydraulic disc brakes.
The disc brake presses on the wheel axle to produce powerful braking under any conditions (dry, wet, muddy, etc.).

Single chainring

This bike is equipped with speed controls that are controlled using the thumb and index finger, allowing effortless changes between the 9 speeds. The 36-tooth single chainring and 11-36 cassette make it easy to shift gears and deal with any kind of hill. With just one control to manage, you can focus on your trajectory.

Front air suspension for cushioning on uneven terrain

This 24" ST 920 bike comes with an air fork that adapts to the child's weight.
Take on new challenging terrain (roots, stones, gravel, etc.) with ease thanks to the travel of the front suspension fork.

Comfort when riding

A saddle with a sporty design, designed with care to adapt to the morphology of children. Combined with an aluminium seat post (sturdy and flexible) for even greater comfort.

Riding position

To hone your steering, we have equipped this mountain bike with a short aluminium stem (70mm) and a 540 mm oversize handlebar. This makes you more precise and responsive on turns.

Aluminium chainset

The new aluminium chainset has a 152 mm crank that is suited to the child's leg length. This light chainset allows you to start pedalling more easily.
The double guard over the chain stops it jumping.

Double-wall rims

The double-walled aluminium rims are light and durable.
For transporting the bike, we've made it easy to attach/detach the front and rear wheels. They are equipped with a quick-release system.
24-inch 1.7 to 2.2 cross-section inner tube with Schrader valve.Pressure indicated on the tyre sidewall (between 2 and 3.5 bar).

Bike accessories

This MTB is equipped with a bell, lighting, wheel reflectors and platform pedals.
The frame is also compatible with other B'Twin accessories:
- front and rear mudguards
- stand
- bottle cage
- bag

Dimensions of the bike ready to use

Length: 160cm.Height: 100cm. Width: 60cm.


12 kg

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Composition / advice

Frame (for bike)
100.00% Aluminium
Stock advice Store the bike in a clean, dry place. Clean and grease the chain regularly. Our advice for before each ride: inflate the tyres to the pressure indicated on the sidewall.
Restricted use : Wearing a helmet is required.

Our commitments

Guarantee : Lifetime (frame, stem, handlebars). Find out more about the bike guarantee.

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Our services

Mountain Bike Rockrider ST 920
Maintenance and repair
Maintenance and repair
Spare parts