two bikes of the same size

Kids Bike Size Guide

Which size Bike infographic

Which Kidvelo bike is right for your child?

A Kidvelo Balance Bike is sized according to wheel diameter.

All our balance bikes require you to know your child’s inseam.

Your child has to be able to sit on the bike seat with both feet flat on the ground.




How to measure inseam

How to measure a child’s inseam

Tip! – Measure their inside leg/inseam with shoes on.

Measure your child’s INSEAM. Leg length is critical when gauging the correct size of bike. Please don’t just size a bike by the age of your child. Everyone is different!

The fit: Remember a balance bike is different to a pedal bike as children’s feet need to touch the ground. When sitting on the bike, kids should be able to put both feet flat on the ground. This helps children learn balance quickly and prevent tip-over accidents.

  1. Stand the rider straight against a wall
  2. Put a book between their legs
  3. Measure from the top of the book straight down to the floor
  4. That is your child’s inseam
Child on Rookie 12

How to choose the correct bike weight to be in proportion to the rider

Experts recommend bikes shouldn’t be more than 30% of your child’s weight.

Heavy bikes over 4 kg will prove challenging to manoeuvre. Young children get frustrated easily. We often hear, “my child doesn’t like their bike,” and when we delve deeper, it is because they have a hefty steel bike with incorrect geometry or stabilisers.

Choose the lightest you can afford without eliminating all the features that make it comfortable to ride.

The Rookie 12″ our lightest bike  At Just 2.89 kg it can be handled comfortably by the smallest riders. The Rookie 14” 2-In-1 Bike is just 4.7 kg without pedals or 6 kilograms in pedal mode and Rookie 18″ Convertible weighs in at just 5.5 Kg, or 7 Kg with the pedals fitted. All are made from top-quality 6061 aluminium alloy, using alloy componentry, to keep the weight down.

12 Wheels lying on the grass

How to consider which size wheels I need

A 10″ wheel may allow for a lower starting seat height, but check the seat height range to get some years’ use out of it.

A quality 12″ wheeled bike may still achieve low seat positions, but the bigger wheel avoids speed wobbles.

Older children need bigger bikes, so consider a 14” or  18” bike.

If the child is a beginner, then a convertible bike is perfect as you get the benefit of learning in balance mode before it magically transforms into a bike with pedals.

Rookie 12 Tyre

What type of Tyres do I need?

Tyres play a crucial role in the performance and comfort level of a bike

The type of tyres will determine the smoothness of the ride and the traction achieved on various surfaces. There are four types of tyres used. These include foam, air, plastic, and rubber tyres.

Pneumatic tyres give the most cushioning and traction and are considered the best all-around solution. Foam tyres are cheaper, lighter and generally puncture-proof. However, they lack traction, something we have witnessed firsthand in off-road riding. Rubber tyres are pretty solid, puncture-proof, and have better traction than foam tyres which aren’t comfortable over rough terrain. Plastic or EVA polymer is the lightest but lowest quality and typically only lasts a year. However, 12-inch pneumatics will offer longevity, far longer than a plastic 10″ wheel.

All Kidvelo Bikes come with Alloy rims and pneumatic tyres, perfect for any terrain riding. Fitted with Schrader Valves, ( same as a car tyre) with a relatively smooth tread pattern to give the best combination of grip and low resistance roll. Our performance wheels are strong and very light.

Do I need Brakes or Not?

Balance bikes work by using feet, safely placed on the ground, to move the bike along and to stop. There is a tendency when buying anything, to think that more features offer better value. When choosing the best balance bike for young children, the easier the bike is to use, the more successful they will be.

Brakes aren’t a good idea for young child as they will stop with their feet, which is intuitive and the safest method. Our experience has shown us that having lever brakes confuse young kids. They don’t know what to pull or they don’t have the finger strength to pull them so the child doesn’t stop quickly enough.

We also noticed that the reach on some brake levers isn’t adjustable enough. Worryingly, we have witnessed the kids taking their hands off the handlebars to pull the lever. For this reason, the Kidvelo 12″ balance bikes do not have brakes. Front and rear braking is introduced on our 14″ & 18″ models designed for older kids.

Child riding a balance bike with feet up on the footrest

Do I need a footrest or deck ?

Our bikes come with a footrest, so feet can be placed correctly when the child is balancing. When just starting out, the child won’t be lifting their feet far from the ground. As the child gets more experienced, they start lifting their feet for long periods of time. This is when the footrest is useful. If you ride your bike, then you wouldn’t ride off a curbside or over a bump with your feet dangling in the air. You would have your feet on the pedals and take the knocks in your legs. If you have feet in the air, it’s your bottom that takes the judders and it’s painful.

A footrest allows children to place their feet when coasting and balancing. Our footrests are designed to be in the correct position to mimic where the pedals will be, and in the convertible bikes, it gets swapped out for the pedal kit. Children are learning balance in the correct position to ride a bike from the start.

Rookie 12 Geometry

Why is bike geometry important

Suitable bike geometry will work with the child to help them learn to balance and manoeuvre, whilst a bike with poor geometry will work against them.

Consider geometry that creates more space between the handlebars and seat post—making it easier to extend the legs for a more comfortable and natural run style while striding. It also means that the handlebar reach is still correct as the child grows bigger.

A low step-over frame is much easier for children to get on and off.  Cyclesprog have covered our bikes in some depth and agrees with us, that we have the perfect geometry.

All our balance bikes are suitable for girls and boys. Kidvelo Bikes have a low step-over frame making them easy to mount.

Rookie 12 Adjustability

Why is a good range of adjustability essential?

All bikes in the Kidvelo range have quick-release clamps (Rookie 12) or allen key clamps (Rookie 14 & 18) to adjust the seat height, and a scale marked on the post so you can easily fine-tune as children grow. You can set the riser handlebars for near or far reach and adjust the height. Our grips are scaled for little hands to give the rider complete control.

Don’t make your purchase based on age alone. There can be a huge difference in leg sizes/inseam between children in the same age group.

Seat height-adjustability is crucial so that the bike will last a few years. When buying balance bikes, you need to check the seat height allows for a slight bend in the knee when feet are flat on the floor, allowing the bike to be walked or run along.

Kidvelo Bike Range

Choose the bike to match your child’s size & ability level

Don’t stress this bit. Our experience has taught us what approximate age children pick up the varying skills required to ride. Kidvelo bikes are sized correctly and consider what skills each age group can handle confidently.

Really young children should start on the Rookie 12 bike without pedals, brakes or stabilisers.

The Rookie 14 (a convertible pedal bike), has front and rear brake levers and transforms into a pedal bike by installing the included pedal kit. Ideal for those moving off their 12″ or just starting to learn.

Older children will need the Rookie 18 version as it is bigger again.

When to transition onto pedals

The rider needs to be comfortable with the weight and handling of their balance bike before transitioning to pedals. At Kidvelo, we make this process simple by giving you a larger, slightly heavier bike that you can use without pedals fitted to start. Get used to the increased weight and size and learn how to use the brakes.

Once your child has mastered balance, our unique conversion bike converts to a pedal bike with the easy-fit pedal kit.

Why buy two bikes when you can have the next generation of kid’s bikes with the Rookie Convertible Balance to pedal bikes. Our unique design gives your child the best chance to learn balance without the complications of pedals but then last for another two years at least, as a pedal bike.

If they aren’t ready and you need to go back a stage,  you can easily remove the pedal kit again.

Green Rookie 12 with a logo and text for Gold Best Balance Bike with Made for Mums

Rookie 12

For riders 18 months to 5 years old
A red balance to pedal bike size guide

Rookie 14

Balance or pedalling
For riders 3 - 6 years

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