Rockrider 100 Kids' 24-Inch Mountain Bike 9-12 Years



Made for

children aged 8 and up (1.35 m to 1.55 m) who are getting started with mountain biking.
We've designed this robust, easy to use (1 chainring) 24-inch children's MTB for discovering mountain biking.

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Ease of useMTB equipped with 6 speeds, with brake levers adapted to children's hands.
Lifetime warrantyB’Twin offers a lifetime warranty on the frame, stem, handlebar and rigid fork.
Warrantyfor life (frame, stem, handlebars, rigid fork). Find out more about the bike guarantee.
Technical Information

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 and designers have designed a brake lever closer to the handlebars that is easier to hold. The brakes are now in reach of little hands!
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.
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. Changing gear to adapt to the terrain is easier than ever!
Frame designed for mountain biking
This robust steel frame is designed to overcome obstacles on all your MTB outings.
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 cover at the back (a bumper) to protect against any impacts.
24" wheels and MTB tyres
To transport the bike, we’ve made it easy to remove and attach the front wheel. It is equipped with a quick-release system. The tyres are designed for mountain biking. The side lugs provide good grip on turns. The recommended tyre pressure is displayed on the tyre sidewall. 24-inch 1.7 to 2.2 cross-section inner tube with Schrader valve.
MTB fittings
This MTB is equipped with a bell, lighting, wheel reflectors and a derailleur guard. The frame is pre-drilled to attach a bottle cage if needed. The frame is also compatible with other B'Twin accessories: - front and rear mudguards - stand - rear pannier rack
Dimensions of the bike ready to use
Length: 160cm. Height: 100cm. Width: 56cm.
Information / Concept / Technology
Frame : 100.0% Steel

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


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Great kids bike
Used for 2 to 8 weeks
He loves it
Good little bike
Used for 2 to 8 weeks
Bought this for my son as his first bike with gears. Chose this as 6 gears seemed manageable to master as opposed to 18+. He likes it a lot and has enjoyed several rides on it. Only downside is the frame is steel instead of aluminium but he doesn't mind as it is not too heavy. Great service from the staff at Decathlon who also assembled it.
Rock rider 100
Used for 2 to 8 weeks
Good bike and excellent service in the shop. My daughter loves it.
excellent valve for money
Used for 2 to 8 weeks
£120 for a 6 gear kids bike. You know they don't respect things at that age so we've not paid over the odds for an expensive bike to be trashed. This one fits the bill perfectly.
Excellent bike
Used for 2 to 8 weeks
Really pleased with this bike for our 8 year old son. Seems sturdy and well made. A few gears which he is delighted with and helps. Slightly heavy gor lifting in/out thr car
Great bike
Used for 2 to 8 weeks
Bought for 8 year old granddaughter as a birthday present and she's never off it.
Versatile bike but only average build quality
Used for 2 to 8 weeks
Bought this for my 8 year old for his birthday and he loves his cycling. We made a 160 mile round trip just to collect it. The first week he used it the front brake fell apart on several occasions (4-5 times a day) which was obviously dangerous. In order to get it repaired I had to do another 160 mile round trip, 4 hours wasted back to Glasgow.

I was told that if it happens again (re-assuring) then there is no point in going back. I had to phone them and they would tell me how to fit it over the phone. Couple of issues with this; I know how to fix brakes and it is not a repair but a replacement part that is needed. Secondly, if it is a further repair then why not tell me when I was in the shop how to fix it?

So, I am effectively left with a kids bike that my son is not keen to ride (the brake has fallen apart a couple of more times since the repair was done), that the shop does not want back and the only effective way to repair it is for me to spend money on replacement parts...

I could have spent a little more on a similar bike but bought it locally. This way I would not have to waste time and money to keep getting it repaired.
nice bike, terrible set-up instructions
Used for 1 week or less
The bike is great for the money - it's very heavy compared to some of the more expensive child focussed brands but at less than half of the price that's to be expected. The set-up instruction manual is a travesty though. It seems to not be be specific to this bike so there's a lot of guesswork involved. Clear instructions that name and identify all the parts and tools at the start then take you through what this bike need to have done to it one step at a time (along the lines of a well known furniture flat-pack retailer) would be much more helpful. We had a random red piece of metal left over and no clue what it was for - I've just worked out from the pictures on the website that it's a guard for the gear derailleur but there were no clues in the instructions at all.
24" wheeled kids bike .
Used for More than 2 years
Great wee starter bike where you don't want the kids to struggle with to many gears and the weight of ineffective suspension .
Good grippy tyres , pedals with easily adjusted seatpost/saddle.
My child has autism and balance isn't great but he took to the bike in no time and is now heading out with me for local rides .
Highly recommend this bike not just for quality but for s fantastic price too.
Late delivery to store.
Used for 1 week or less
This is the fourth bike I have purchased from Decathlon side December last year. As per the first three purchases this bike has been much appreciated by the recipient grandchild. It's is very well made and I would recommend it to anybody looking to purchase an excellent bike at an excellent price.
Sadly, I believe you were let down by a problem in delivery to the Crawley store. I was advised that the bike would be available for collection the day after I ordered and paid for it. When I visited the store to collect the bike your staff, who incidently were as helpful and friendly as always, were unable to track my order!
As I live be over 25 miles from the store I was disappointed to say the least.
My score of average does not reflect on the quality of the bike nor in any way on your staff in Crawley.
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