Your child getting a new bike can be a great moment and a memory that rides with them

through life. So knowing your kids' bike basics is important to make sure you get the best boys’ bike or girls’ bike for your little one.

Unfortunately it's not as easy as picking a colour and grabbing the nearest option. When it comes to children’s bikes there's quite a lot to take into consideration. Do you want a balance bike for toddlers, general balance bike or perhaps a Btwin balance bike specifically? Or maybe your little one is beyond balance bikes and you need to think about a kids’ bike size guide to get the right model for your little rider?

A Decathlon kids' bike can get you what you need. And by that, we don't just mean something that takes bike safety for kids into account, but also something that puts a huge smile on your little one's face (and a kids' cycle helmet on their head, of course). This guide will cover everything you need to think about before buying the best kids' bike for the young cyclist in your life.

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Using a size guide will help you understand the correct size bike to get your child.

What size bike do I need for my child?

This question is integral to buying a child's bike. If it's balance bikes you're after then you may be able to shop by age, making it relatively simple to find the right one. Decathlon balance bikes cover a wide age range so there is usually something for most little ones. But if you're looking for a kids' pedal bike but are not sure which to go for, size is a great place to start. This size guide will help you match the correct size bike for your child:

Bikes for kids aged 2-4 years or child height: 3ft-3ft 5”

12” wheels

These models will often be compatible with stabilisers and come with either coaster brakes or one brake lever.

Bikes for kids aged 4-7 years or child height: 3ft 5"-3ft 9"

14”-16” wheels

All of these bikes have rubber tyres with inner tubes and provide a smoother ride than smaller bikes, ideal for when kids are starting to become a little more independent on their bike.

Bikes for kids aged 7-10 years or child height: 3ft 9"-4ft 5"

20” wheels

Progressing a little further, these bikes will sometimes feature gears and may even have suspension. By this point kids are likely to be confident on a bike and ready to hold their own on longer bike rides.

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Children aged 10-13 need 24” wheels on their bikes.

Bikes for kids aged 10-13 years or child height: 4ft 5"-5ft

24” wheels

At this point, kids are growing quickly and bikes in this range are generally packed with the same features as an adult bike, but will simply have a smaller frame.

Bikes for kids aged 13 years and over or child height of 5ft+

Small adult frame bikes

As they hit their teens, most kids are ready for small adult bikes, which means the sizing changes from wheel size to frame size. 13" or 14" frames generally suit best.


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Finding a safe space for your children to practice cycling is essential when they are still learning and finding their balance.

Can children ride on the road?

Legally, no one is allowed to ride on the pavement, so that leaves either the road or off-road on the grass. For children, that can be dangerous, which is why it's a good idea to find a safe area to ride, like a car park out of hours – or, ideally, designated cycle paths. Even cycle paths are often split for both cyclists and pedestrians so be wary if your child is still finding their balance.

Do children have to wear a kids' cycle helmet?

In the UK there is no law that says your little one has to wear a kids' cycle helmet but, of course, they are better protected with one on – especially in the case of younger children where their skulls are not fully formed and can be particularly susceptible to impacts. If your child is riding on tarmac, and at any kind of speed, a helmet should really be a requirement. Falling off is a part of learning but it needn’t be dangerous as long as you take safety precautions.


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It is worth bearing in mind that if you choose a bike your little one can grow into, then it will last longer.

How much should you spend on a kids bike?

Pricing of bikes varies with larger bikes costing extra in most cases as there are more complex parts and more materials. It’s worth bearing in mind that if you choose a bike your little one can grow into then it will last longer, which means you might be able to get away with buying one bike rather than two over a period of time.

While some brand names are better known than others, all kids bikes at Decathlon are safety tested so however much you spend, your child will be safe.

What type of bike should you buy?

It can be quite daunting trying to work out what type of bike to buy, especially if you don’t cycle yourself. There are lots of different styles of bike to choose from and each has its own benefits depending on the type of rider the bike is for. Here are some of your options…


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Balance bikes are a great way to teach children from age two and upwards how to balance on a bike.

Balance bikes

Balance bikes are bikes without pedals. They help to teach children from age two and upwards how to maintain balance on a two-wheel bike as they propel themselves along with their legs. It is said that starting with a balance bike can actually make it easier for children to learn to ride a two-wheeler without having to go through a period of using stabilisers. When children use stabilisers they tend to become reliant on them, at the expense of using their balance, and this can often make it more difficult to remove the stabilisers. A balance bike is designed to give kids that ‘balance confidence’ earlier.

Children’s bikes

From balance bikes and tricycles, the next step is their very own bike. While the style of bike isn’t important for really young riders, as they get older their style of riding will change and more options will become available to them. Mountain bikes are perfect for off-road riding. Road bikes are built for speed and distance with slimline tyres and lightweight frames making them perfect for long weekend rides. Hybrid bikes are a combination of a mountain bike and road bike and can handle going from pavement to trail with ease – the perfect all-rounder.


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Decathlon kids’ bikes: the essential buying guide

Are bikes delivered fully assembled?

To avoid damage and scratching to the bikes, they aren’t built before delivery. Balance bikes and smaller kids bikes take very little assembly, but small adults bikes may require a little more attention. There are two options for the build of your bike:

Order for click and collect

Click and collect orders are handled at the stores, which means that the team of in-store cycle experts will build your bike for you ahead of collection.

Build your bike at home

Decathlon bikes arrive with step-by-step instructions that will help you build your bike at home. In the majority of cases, you will only need to attach the handlebars and the pedals to a child's bike. For larger bikes, this video will help you build your bike. If you’re still having trouble, you could choose a bookable video call where you are walked through the steps you need to take to put your bike together.


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Decathlon offers a lifetime guarantee on all metal-framed bikes, rigid forks, handlebars and stems.

Peace of mind when ordering

Decathlon offers a 365 day return period and the online returns service is free. That means

you won’t be out of pocket if you want to return your item.

Decathlon bike warranty

Decathlon is so confident in its bike quality, you get a lifetime guarantee on all metal-framed bikes, rigid forks, handlebars and stems. Carbon bike frames also come with a five-year warranty. That means if anything goes wrong with the bike during that time, just bring it back and you can get help right away.