Decathlon Kids’ Bikes: Everything You Need to Know About BTWIN and Rockrider

Understanding the ranges: what do the numbers mean?

Before diving into the individual Decathlon kids' bikes, it helps to understand how both BTWIN and Rockrider organise their ranges. Once you know the system, choosing the right bike becomes much more straightforward.

Both brands use a numbering system across their ranges: 100, 500 and 900. You will see these numbers in the model names throughout this guide, and they indicate where each bike sits in terms of specification and price.

• The 100 series is the entry-level range, with a focus on affordability. Bikes in this series tend to be heavier with more basic components. They work well as a budget-friendly starting point, but it is worth knowing that the extra weight can make riding feel harder, especially for younger or less confident riders.
• The 500 series is a step up. These bikes are better equipped and usually lighter, which can make a real difference to how much your child enjoys riding. If your child is gaining confidence or tackling more varied routes, the 500 series will make the experience smoother and more enjoyable.
• The 900 series contains the lightest and best-equipped bikes in the range. While they sit at the top of the BTWIN and Rockrider ranges, they are still significantly more affordable than many other premium kids' bike brands, making them a great option for families who want top performance without a premium price tag.

In some cases the numbers vary slightly, as with the Rockrider EXPL 120, but the same principle applies: the higher the number, the lighter and better specified the bike.

Are Decathlon kids' bikes any good?

In short, yes. At Cycle Sprog, we only recommend bikes we would be happy for our own children to ride, and both BTWIN and Rockrider feature regularly across our best kids' bikes buyers guides precisely because they offer genuinely good quality at prices that are hard to argue with.

That said, Decathlon kids' bikes are not without compromise. The entry-level 100 series bikes are heavier than more premium brands, and if your budget stretches to it, stepping up to the 500 or 900 series makes a noticeable difference to how enjoyable the bike is to ride, particularly for younger or less confident children where every extra kilogram makes handling harder.

Where Decathlon really stands out is at the top of their range. The 900 series bikes are significantly lighter and better equipped than you might expect for the price, and while there are other brands offering even lighter options with more refined components, they come at a considerably higher cost. For families who want a capable, well-designed bike without paying a premium price, BTWIN and Rockrider hit a sweet spot that very few other brands can match.

We have reviewed several bikes from both ranges, and our honest verdict is that Decathlon kids' bikes represent some of the best value for money in kids' cycling. If budget is your main priority, the range also includes some of the cheapest kids' bikes on the market that are still good quality.

BTWIN kids bikes

BTWIN covers the full range of everyday cycling for children, from the very first steps on a balance bike right through to hybrid bikes for older kids and young teens. Here is a closer look at each part of the Decathlon BTWIN range.

Ride-ons and balance bikes

At the very start of their cycling journey, children as young as one can use ride-ons and balance bikes to develop the key skills that will set them up for a lifetime of cycling.

The Decathlon 2-in-1 age-adjustable baby ride-on starts out with four small wheels, giving very young children the confidence to get moving, before converting into a two-wheeled balance bike as they progress.

Once they have mastered the ride-on, they should be ready for a 12-inch BTWIN Runride balance bike. The Runride 100 is the most basic model, suitable for use close to home. The Runride 500 is a better option if they are making short trips with you along the road, as it comes with bearings for a smoother ride. 

At the top of the range, the Runride 900 has a lightweight aluminium frame and pneumatic tyres for more grip and comfort on pavements and uneven terrain.

If your child is learning at a later stage or is tall for their age, BTWIN has two 14-inch 2-in-1 options that function like the Runride but are bigger and can be converted to a pedal bike. 

The Discover 500 14-inch Learning Bike has a steel frame and weighs 6.6kg, while the Discover 900 14-inch Kids' Bike has an aluminium frame and at 5.6kg is a full kilo lighter, which is a significant difference on a bike this small. Both can be switched between balance and pedal mode in seconds without tools, and feature brake levers designed for small hands.

We have reviewed and can really recommend the BTWIN 2-in-1 age-adjustable baby ride-on.

Decathlon’s small pedal bikes for learning to ride

Once your child is ready to start pedalling properly, the BTWIN Discover range has options for every stage of early riding.

At the 14-inch size, the 2-in-1 options we mentioned in the balance bike section above are worth considering even if you think your child is ready to pedal. 

The ability to switch between balance and pedal mode in seconds without tools means that if your child turns out to need a little more time on two wheels before they are ready for pedals, you have not backed yourself into a corner. The Discover 500 14-inch Learning Bike and the Discover 900 14-inch Kids' Bike are both designed with this flexibility in mind. 

If you are confident your child is ready to pedal straight away and want the most affordable option, the Discover 100 14-inch is also available as a straightforward pedal-only bike.

The next stage up is the 16-inch Discover range, designed to help young pedallers find their confidence. 

The 16-inch Discover 100 is the entry-level model, extremely affordable and fitted with Stop Easy V2 brakes. At the top of the range, the aluminium 16-inch Discover 900 weighs just 6.6kg, which is good going for a bike at this price point. Take a look at our BTWIN 16-inch Discover 900 first impressions review to see it in more detail.

When choosing between the Discover models, the same numbering principle applies as across the rest of the range: the 100 series will do the job at the lowest price, but if your budget stretches to the 500 or 900, the lighter weight will make a noticeable difference to how much your child enjoys riding, particularly in the early stages when confidence is still building.

BTWIN Riverside hybrid kids bikes

The BTWIN Riverside range is Decathlon's hybrid bike offering for children, designed for all-round use combining paved routes with a little light off-road. 

It covers 20-inch to 26-inch wheel sizes and is suitable for children roughly between the ages of 6 and 12, though as always, height is a better guide than age when choosing the right size.

At the 20-inch size, the single-speed Riverside 100 is the entry-level model, simple to use and perfect for riding in flatter areas. The BTWIN 500 20-inch Hybrid Bike is a step up with 6-speed gearing, while the Riverside 900 20-inch is around 2kg lighter thanks to its aluminium frame and has 8 gears for tackling hills.

In the 24-inch range, the Riverside 100 is the entry point, with a 6-speed twist shifter and V-brakes. The Riverside 500 24-inch is a great option for riding to school, coming fully equipped with a front light, kickstand and a more comfortable saddle.

For older children and young teens, the Decathlon 26-inch Hybrid Bike Riverside 900 is built around a lightweight aluminium frame, has 8-speed trigger shifting, a Selle Royal saddle for comfort, and larger wheels for fast and efficient rolling. Take a look at our BTWIN 26-inch Riverside 900 review for more detail on this particular bike.

BTWIN kids' city bikes

If you live in a relatively flat area, or your child is simply drawn to the classic city bike look, Decathlon has some stylish options with 20-inch and 24-inch wheels.

The Decathlon city bike range has a classic Dutch-inspired style, with a low step-through frame, an upright riding position and a basket on the front. Both the 20-inch Kids' City Bike 500 and the 24-inch Kids' City Bike 500 are designed for leisure cycling on paved and light gravel paths, come fully equipped with mudguards to keep your child dry, and have 6-speed gearing.

They are not designed for off-road use or for children who want to go fast, but for relaxed rides around town or along cycle paths, they are a practical and good-looking choice.

Decathlon E-three 500 longtail electric cargo bike

It is not a kids' bike, but no guide to Decathlon's family cycling range would be complete without mentioning the E-three 500 longtail electric cargo bike. For any family that wants to travel together by bike, having a capable and affordable cargo bike in the mix makes the whole thing significantly easier.

The Decathlon E-three 500 is designed to be flexible and adaptable to different family needs, and comes with an ecosystem of compatible accessories including a baby carrier, cushion, box and luggage carriers. Available in three colours, it is priced at £2,499.99, making it one of the more affordable electric longtail cargo bikes on the market. It has a built-in front basket, a double kickstand and a total carrying capacity of 208kg.

We have reviewed the E-three 500, though it is worth noting that our review was of an earlier specification of the bike, so some details may differ slightly from the current model. Take a look at our Decathlon E-three 500 longtail cargo bike review for an in-depth look at how it rides.

If you are looking for the best cargo bike for families but do not have an unlimited budget, this is a very strong option worth considering.

Rockrider kids' mountain bikes

If your child has caught the mountain biking bug, or you want to give them a bike that can handle more than just the school run and family bike rides, the Decathlon Rockrider range is worth a close look.

Rockrider is Decathlon's dedicated off-road brand, and the kids' range covers wheel sizes from 20-inch through to 26-inch, suitable for children roughly between the ages of 6 and 12. As with the BTWIN range, height is a more reliable guide than age when choosing the right size.

The range is built around the EXPL series, and covers everything from a first taste of off-road riding through to more capable bikes for children who are riding regularly on trails and rougher terrain.

Understanding the Rockrider kids mountain bike range

The same numbering system that applies across the BTWIN range also applies to Rockrider, with higher numbers indicating lighter weight and better specification. The range covers wheel sizes from 20-inch through to 26-inch, with the EXPL series sitting at the heart of it, designed for exploration and trail riding at every level.

20-inch Rockrider mountain bikes

The 20-inch Rockrider range from Decathlon is aimed at children roughly between 120cm and 135cm tall, typically around 6 to 9 years old, and offers three models at different price and specification points.

The EXPL 120 is the entry-level option, a rigid bike with 6-speed gearing that will give a child their first taste of riding off-road. It is a capable bike for the price, and better than many alternatives at a similar price point, but the lack of a suspension fork means it will feel noticeably less comfortable on rougher terrain than the models above it. For a child who wants to ride on proper trails regularly, it is worth stretching the budget further if you can.

The EXPL 500 introduces a suspension fork, which takes the edge off rougher ground and makes trail riding noticeably more comfortable and enjoyable for young riders. It is a significant step up from the EXPL 120 in terms of how it rides off-road.

At the top of the 20-inch Rockrider range, the EXPL 900R offers a lightweight aluminium frame, a rigid fork and mechanical disc brakes. We have reviewed this bike in detail and can recommend it highly for young riders who are riding regularly on trails. Take a look at our Rockrider 20-inch EXPL 900R review for the full picture.

24-inch Rockrider mountain bikes

The 24-inch Rockrider range is aimed at children roughly between 135cm and 150cm tall, typically around 9 to 12 years old. At this size the range narrows to two models, both part of the EXPL series.

The EXPL 500 is the entry point, with 7-speed gearing, V-brakes and a suspension fork. It has a slightly heavier steel frame than the model above it, but it is a solid and capable trail bike for a child who is riding regularly off-road.

At the top of the range, the Rockrider EXPL 900 steps up to a lightweight aluminium frame, 9-speed gearing and hydraulic disc brakes. Hydraulic brakes are a meaningful upgrade at this level, giving more consistent and reliable stopping power in wet and muddy conditions, which matters a great deal when riding off-road in the UK.

26-inch Rockrider mountain bikes

The 26-inch Rockrider range is aimed at older children and younger teens, roughly between 150cm and 165cm tall. As with the 24-inch range, there are two EXPL models to choose from.

The EXPL 500 is the entry point, a 7-speed aluminium mountain bike with V-brakes and 2-inch wide tyres for a firm grip on varied terrain. It is a capable and affordable option for a child who is riding regularly on trails and starting to take their off-road riding more seriously.

At the top of the 26-inch Rockrider range, the EXPL 900 introduces hydraulic disc brakes and 9-speed gearing, making it a genuinely capable trail bike for a young rider who is out in all conditions. As with the 24-inch EXPL 900, the hydraulic brakes are a particularly worthwhile upgrade for UK riding, where wet and muddy conditions are a regular reality rather than an occasional inconvenience.

BTWIN and Rockrider helmets and clothing

Decathlon's cycling accessories range is as well thought out as their bikes, and well worth exploring once you have found the right bike for your child.

The BTWIN clothing range covers everything a young rider might need throughout the year, from summer mitts and winter gloves through to jerseys, shorts and waterproof jackets. Take a look at the full Decathlon kids' cycling clothing range to kit your child out for their riding adventures.

For helmets, there is a good selection of affordable options suitable for everyday riding, as well as Rockrider helmets designed specifically for off-road use. Take a look at the full range of Decathlon kids' bike helmets to find the right fit.

If you are cycling with a very young child on board, it is useful to know that BTWIN produces one of the smallest and most affordable baby and toddler helmets on the market. We have reviewed the BTWIN 500 Baby Helmet and our testers love it.

We hope this guide has helped you navigate the Decathlon kids' bike range with confidence. If you have any questions about any of the bikes mentioned, feel free to leave a comment below and we will do our best to help. Happy riding!