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20 Inch Kids Mountain bike Rockrider ST 500 6-9 Years old

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Sale price: 1,300 SAR

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This mountain bike is designed for children who are aged 6 to 9 and planning to go biking often. It's suitable for kids with heights between 120 and 135 cm.

For comfortable rides on rough terrain, we've equipped this 20" MTB with a suspension fork. Easily overcome slopes with the 6 speeds.

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Sale price: 1,300 SAR

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Product Features

A photo of the 20 Inch Kids Mountain bike Rockrider ST 500 6-9 Years old in use

Ease of use

Equipped with a grip shifter to easily change gears (6 speeds).

Brake control

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


Suspension fork. Skinwall tyres for less weight, with side knobs.

Cycling comfort

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

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Product Reviews

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2473 reviews

20 Inch Kids Mountain bike Rockrider ST 500 6-9 Years old
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Got this (from Santa) for my 6 year old. Pedal fell off on first outing! How dyou explain that to a child. Would give 1 star but I’m giving decathlon the benefit of the doubt that maybe this was just an oversight by the ‘elf’s’.

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Rockrider st 500 kids bike

Great price.quality product. Excellent customer service. Thankyou.

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Thank you for your kind words, Anthony.

We really appreciate you taking the time to leave us your feedback.

Have a great day and we hope to see you again soon.


Sports Advisor (Customer Service)

Decathlon Wednesbury

Decathlon UK Limited. Company number: 03140144. VAT number: GB679262296.

Registered office: 9 Maritime Street, London, SE16 7FU.

Christmas present

Looks a good stable bike. Great service from all the staff that was involved with the purchase.

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Mountain bike

Great bike and first one for my grandson and he loves it

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Rockrider ST 500 kids. Great value for money

Very good value for money and excellent professional customer service at Decathlon Warrington. I highly recommend this product and this store.

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Christmas bikes for Twins

Excellent quality bike (I needed two for my twin grandsons) for Christmas. I had seen bike online and was staying with my daughter in Suffolk when we visited Cambridge Decathlon to look at bikes, I was so impressed by both the bike and the helpfulness of staff I purchased immediately. Alison a happy nan

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Very strong bike, but the accessories like mud guards were very flimsey. Buying of helmet fitted when bought within weeks became small and could not extend the straps anymore, The bottle holder recommended does not hold properly, Bit disappointed as this was bought for my Grandsons birthday and he chose the extras which your sales advisor advised.

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Mountain bike

Brilliant bike shame my grandson has got to wait until Christmas

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My 6 yr old loves it... The gears are so good and easy to use. The style of this bike is so cool and bright.

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I bought my son a bike for his 6th Birthday. He sat on it and the seat wasn’t fitted properly so I thought nothing is it and fixed it myself, he hadn’t ridden it for more than 5 minutes and the peddle fell off. Either the parts are faulty, or the staff member is.

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Kids Bike

excellent cycle

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Magic first geared bike

Son stepping up and not looked back spot on and not stupidly dear despite good components

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Bought for my 8 year olds birthday. He absolutely loves it. Great quality as always with Decathlon bikes.

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Additional Product informations



  • 100% Steel

Frame designed for mountain biking

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

Front suspension to cushion unpredictable terrain

Take on new challenging terrain (roots, stones, gravel, etc.) with ease thanks to the travel of the front suspension fork.

Changing gear

This bike is equipped with a grip shifter to change between the 6 speeds: an easier, safer system as the child's hands stay on the handlebars.This makes changing gears to match the terrain simple and easy!

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.


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 crank is covered to prevent the child from coming into contact with the metal part.The double chain guard prevents the chain from derailing.

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!

20" wheels and mtb skinwall tyres

The tyres are designed for mountain biking. The lateral lugs provide good grip on turns. The tyres use SkinWall technology. This process reduces their weight and makes them more flexible, which increases performance, grip and comfort.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.

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- saddle bag- stabilisers:

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 mmSeat tube length: 285 mmChainstay length: 360 mmSeat post length: 300 mmHead angle: 68.8°

Photos non binding

For the drive train parts (freewheel and derailleur), the photos or videos provided on the product description show a Shimano derailleur and a Spark freewheel. However, because of procurement issues, an equivalent, derailleur and cassette from a different brand may be present on the bike.

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