20 Inch Kids Mountain bike Rockrider ST 100 6-9 Years old - White


This bike is designed as an introduction to mountain biking for children from 6 to 9. It's suitable for kids with heights between 120 and 135 cm.

This single-speed bike is designed for ease of use. The frame, stem, handlebar and rigid fork are guaranteed for life.

Color: WHITE

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Product benefits

Ease of use

This single-speed bike is simple and effective on flat terrain.

Brake control

New Easy Break brake levers are sized for children's small hands.


Tyres with side lugs for good grip in the turns.

Cycling comfort

A saddle with a sporty design, sized especially for children.

Technical information

Frame designed for mountain biking

Our engineers have designed a new sturdy steel frame. The frame's rear chainstays are short, making the bike responsive and easy to handle.

Why have we created a brake lever specifically for children?

Because children have smaller hands than adults, it's not always easy for them to reach the brake lever. This is why our engineers designed a brake lever that is closer to the handlebars and thus easier to hold.

Single speed

With only one speed, the bike is simple and remains effective on flat terrain.

Controlled braking

Two V-Brake pads for effective braking.
These brakes are composed of callipers that exert more or less pressure on the rim to slow or stop the rotation of the wheels.

A reinforced, ergonomic saddle

A saddle with a sporty design, designed with care to adapt to the morphology of children. It is equipped with a plastic section on the rear (a bumper) to protect against any impacts.

Riding position

When mountain biking, it is important to control your path. To make it easier for children to learn, our engineers installed a handlebar and stem that are combined into a single steering block. This eliminates the needs for adjustments, so they can stay focused on the road!


The new chainset has a 140 mm crank that is designed for a child's leg length. This chainset allows you to start pedalling more easily.
The double chain guard prevents the chain from derailing.

20" wheels and MTB tyres

The tyres are designed for mountain biking. The lateral lugs provide good grip on turns.
The recommended tyre pressure is indicated on the side of the tyre (2 to 3.5 bars). 20" inner tube, 1.7" to 2.2" Schrader valve.

MTB fittings

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
- saddle bag
- stabilisers: https://www.decathlon.co.uk/20-and-24-stabilisers-id_8550741.html

Dimensions of the bike ready to use

Length: 140cm.
Height: 80cm.
Width: 54cm.

What if I order online?

For smoother shipping, our bikes come with their pedals removed and the handlebar unscrewed (instructions and tools are supplied)

Frame dimensions

Top tube length: 431.6 mm
Seat tube length: 285 mm
Chainstay length: 360 mm
Seat post length: 300 mm
Head angle: 68.8°


for life (frame, stem, handlebars, rigid fork). Find out more about the bike guarantee.


11 kg

Product concept & technology

Product Composition

Frame 100% Steel


Store the bike in a clear, dry place. Clean and grease the chain regularly. Our tips for before each ride: inflate the tyres to the pressure indicated on the sidewall.

User Directions

Wearing a helmet is required. Max user weight: 80 kg


To have more informations about this product, consult the notice


20 Inch Kids Mountain bike Rockrider ST 100 6-9 Years old - White
20 Inch Kids Mountain bike Rockrider ST 100 6-9 Years old - White
20 Inch Kids Mountain bike Rockrider ST 100 6-9 Years old - White
20 Inch Kids Mountain bike Rockrider ST 100 6-9 Years old - White


Q:How to assemble your bike?

A: Everything you need to know about making sure your bike is comfortable, secure and ready to ride.

Q:Do you offer a Cycle To Work scheme?

A: Find out everything you need to know about way of getting to work that’s for good you and the environment. Check Here
Products sold and shipped by Partners are not eligible for Cycle to work Schemes

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