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Welcome to our comprehensive guide on kids bikes components! When it comes to choosing the best kids bike for your child, understanding the various components is a great help.  

From frames and wheels to brakes and gears, each part plays a vital role in your child's cycling experience.    

In this blog, we will delve into the world of kids bikes components, providing you with all the essential information you need to understand how bikes work. Let's dive in and discover everything you will ever need to know about kids bikes components! 


A frameset is a fundamental component of a bicycle that serves as the backbone of the entire structure. It consists of several key elements that work together to provide stability, strength, and control. Here's a breakdown of the different parts of a frameset:  

frame set


The main part of a lightweight kids bike frameset is typically made of aluminium forming the structure of the bicycle. It determines the bike's overall shape, size, and geometry. All bicycle frames from each of our suppliers are extensively tested from 3 of the best assembly factories in the world to guarantee strength and safety.

The aluminium frames provided by our top 3 junior bike brands, notably Woom bikes, feature butted tubing. This is where the outsider diameter of the frame remains a constant shape, but the internal wall thickness varies. This process is costly to manufacture but produces a lighter frame and more comfortable ride without sacrificing frame strength. 

  • Top Tube: The top tube is a horizontal tube that connects the head tube to the seat tube. It plays a role in determining the bike's overall length and contributes to its strength and rigidity.  
  • Down Tube: This is a vertical tube that connects the head tube to the bottom bracket shell. It is one of the primary load-bearing tubes of the frameset, providing structural integrity and stability.  
  • Head Tube: The head tube is located at the front of the frameset and houses the headset. It connects the top tube, down tube, and fork, allowing for smooth steering and control.  
  • Seat Tube: The seat tube is a vertical tube that holds the seat post and saddle. It determines the rider's seating position and can have an impact on comfort and pedalling efficiency.  
  • Chainstays: These are two horizontal tubes that connect the bottom bracket shell to the rear dropouts, where the rear wheel is attached. They provide stability and help transmit power from the pedals to the rear wheel.  
  • Seatstays: These are the two tubes that connect the seat tube to the rear dropouts. They contribute to the overall structural integrity of the frameset and help absorb vibrations.  

At Bike Club, we offer bikes with kid-specific geometry and comfortable frame sizes for your child to ride. We have bike sizes for kids in all age ranges.  


The fork is located at the front of the frameset and holds the front wheel. It consists of two blades that extend downward from the steerer tube, providing steering control and absorbing road vibrations.  

Modern forks usually have straight blades, producing a lighter fork and subjectively, a more modern design, such as those found on our Forme and Woom bike brands. 

Most lightweight kids bikes feature aluminium forks, although some manufacturers use a combination of a steel fork and an aluminium frame to help reduce the cost. 


The headset is the set of bearings that allow smooth rotation between the frame's head tube and the fork's steer tube. It enables the rider to steer the bicycle. 

Most of the premium kids bikes at Bike Club feature an integrated headset, meaning the bearings are hidden inside the frame to prevent them from becoming damaged or corroded by the weather conditions.


The crankset is a critical component of a bicycle's drivetrain, converting the rider's pedalling motion into forward propulsion. Its design, including the length of the crank arms and the number of chainrings, affects the bike's gearing and efficiency.

crank set - bike club  

  • Crank Arms: These are two long arms that extend from the bottom bracket spindle. They are responsible for transferring the rider's pedalling force to the chainrings. Pedals are attached to the crank arms.  

  • Bottom Bracket: The bottom bracket is the component that houses the bearings and spindle where the crank arms attach. It provides support and allows for smooth rotation of the crank arms.  

  • ChainringsThis is the toothed disc attached to the right hand crank arm. They are typically labelled with the number of teeth they have. The chainrings engage with the bicycle's chain, transmitting power from the rider's pedalling to the rear wheel. To prevent adding any unnecessary weight, lightweight kids bikes are rarely seen with more than 1 chainring. 

  • Chainring Bolts: Small bolts that secure the chainrings onto the crank arms. They ensure that the chainrings are securely attached and properly aligned.  

Crank length primarily depends on the size and type of bike. All lightweight first pedal and hybrid bikes added to the Bike Club fleet are selected to ensure the cranks are much shorter to enable more efficient pedaling better suited to a child’s shorter inside leg measurement and also to allow the use of a larger, easier to ride wheel size, at a younger age. 

Brands such as Forme, Woom and Frog often reference “Q-factor” in their product descriptions. Q-Factor sounds complicated, but it literally means the measurement between the 2 cranks. In other words, how far apart our feet are when pedaling. The optimum Q-Factor on smaller kids bikes is important to ensure the pedals are positioned in line with a child’s natural stance to deliver maximum power when pedaling, also helping to prevent injury.   

Handlebars & Stem  

The combination of handlebars and stem determines the rider's comfort, control, and riding position on the bicycle.   

handle bar diagram - bike club

  • Handlebars: The component that the rider holds onto for steering and control. They come in various shapes and styles, including drop bars, flat bars, and riser bars.   
  • Stem: The stem is the component that connects the handlebars to the steerer tube of the fork. It provides the necessary support and affects the handlebar height and reach.  

Road bike handlebar position is lower compared to other bike types, promoting a more aggressive and aerodynamic riding posture. They also feature drop handlebars. 

Handlebars on Bike Club first pedal and hybrid kids bikes are often narrower and lighter than a typical kids bike. A combination of real world and lab-based testing has been undertaken by each of our 3 primary kids bike brands. 

Saddle & Seat Post  

saddle and seat post

  • Saddle: The part of the bicycle where the rider sits. It is designed to provide comfort and support during the ride. A smaller saddle, without any excess and unnecessary padding or length, is a great way to save weight on a kids bike.

  • Seat Post: The seat post is a vertical tube that inserts into the frame's seat tube and holds the saddle. It allows for height adjustment, allowing riders to find their desired saddle height for proper leg extension and comfort.   

  • Saddle Clamp: This attaches the saddle to the seat post. It typically consists of two or more bolts that secure the saddle rails to the seat post clamp. The saddle clamp allows for fine-tuning of the saddle's fore-aft position and tilt angle.  

Gear Shifters & Brake Levers  

Gear shifters and brake levers are crucial components for controlling the bike's speed and changing gears. Our kids bikes with gears usually have trigger shifters.

gear shifters & brake levers - bike club 

Gear Shifters 

Gear shifters are controls that allow the rider to change gears. They adjust the bicycle's gear ratio to adapt to different terrain or riding conditions. There are several types of gear shifters, including:  

  • Trigger Shifters: These consist of two levers that are operated by the rider's thumbs or index fingers. Pushing or pulling the levers initiates the shifting action, moving the chain across different gears. Trigger shifters are usually much easier for small hands to operate with very little force required.

  • Grip Shifters: Grip shifters are twist-style shifters located on the handlebar grips. Rotating the grip in one direction or the other changes gears.

  • SureShift: As used exclusively on our Forme bikes brand offer the perfect solution for easy gear changing. Even trigger shifters are often designed for adult hands, not little hands. Frog have a slightly longer lever on their gear bikes but the colour coordinated SureShift lever extenders featured on the Forme Kinder bikes offer the best ergonomic and cognitive solution to gear changing. The bright colour makes it easy for the rider to identify which trigger shifter helps them change to an easier gear whilst the extension shortens the level arc making it super easy for tiny thumbs to operate.

Road bike gear shifters are commonly integrated with the brake levers, known as brifters. On most road bikes riders do not have to move their hands from the handlebars to shift gears.    

Brake Levers 

Brake levers are the controls that engage the bicycle's braking system. When squeezed, the brake levers activate the brakes, applying pressure to the brake pads or calipers to slow the bike. Brake levers come in different styles, including:  

  • Mechanical Brake Levers: Used with cable-actuated braking systems, such as rim brakes or mechanical disc brakes. When the lever is squeezed, it pulls the cable, engaging the brakes.  
  • Hydraulic Brake Levers: These are used with hydraulic disc brakes. When the lever is squeezed, it activates hydraulic fluid, which applies pressure to the pistons, resulting in braking action.  

Disc brakes add unnecessary weight and complexity to a lightweight kids bike which does not require the powerful stopping power of hydraulic disc brakes. Disc brakes are better suited to heavier adult riders or offroad bikes being used for much more technical riding than a kids hybrid or first pedal bike should be used for. 


Pedals of course play a vital role in transmitting power and control. They are the components of a bicycle that the rider's feet rest on and use to propel the bike forward.   

Pedals are attached to the crank arms of the bicycle's drivetrain. There are two main types of pedals:  

  • Platform Pedals: Platform pedals are flat pedals with a large surface area that provides a stable platform for the rider's feet. They are commonly used in casual and leisure cycling, as well as in disciplines where quick foot engagement is necessary, such as BMX biking or downhill mountain biking.   
  • Clipless Pedals: Clipless pedals, despite the name, actually require the use of special cycling shoes with cleats that clip into the pedal mechanism. The cleats on the bottom of the shoes engage with the pedals, creating a secure connection between the rider and the bike. Clipless pedals offer enhanced power transfer, particularly in road cycling and mountain biking.  

Finally, the pedal axle is the metal rod that extends from the pedal body and attaches to the crank arm. It allows the pedals to rotate freely as the rider applies force while pedalling.  

Our smallest bikes, balance bikes, do not come with pedals. The focus is on the child maintaining their balance, and preparing them for their first child bike with pedals. 

Wheels & Tyres  

wheel and tyres diagram - bike club

Wheels and tyres greatly impact the ride quality, performance, and handling of a bicycle.    


The wheels are one of the most essential components of a bicycle, providing support, stability, and facilitating forward motion. A wheel consists of several parts:  

  • Rim: The outer circular part of the wheel that holds the tire in place. It provides a surface for the tire to rest on and supports the spokes.  
  • Spokes: Spokes are thin, metal rods that connect the rim to the hub. They provide structural support and help distribute the rider's weight and forces evenly across the wheel. The tension of the spokes determines how ‘true’ the wheel runs, i.e. how circular its motion is.  
  • Hub: The hub is the central part of the wheel that houses the bearings. It allows the wheel to rotate smoothly on the bike's axles. Some of the most premium junior bike brands such as Woom, feature fully sealed bearings to ensure minimum rolling resistance and protection from all weather conditions. 
  • Axle: This is a rod that runs through the hub. It connects the two ends of the wheel to the bike's frame or fork.  

Build quality – Forme, Frog & Woom each have notoriously high quality wheel builds. The Forme bikes assembly factory uses some of the most sophisticated, laser operated wheel building machines in the world and manufactures for some of the worlds largest bicycle brands. Wheel building is also a design feature Frog prides itself on. 


Tyres are the rubber outer layer that encases the rims and come into direct contact with the riding surface. They provide traction, shock absorption, and influence the bike's overall performance depending on their size and tread type.

There are various types of tyres, including:  

  • Clincher Tyres: Clincher tyres are the most common type and have beads that fit into the rims, requiring inner tubes to hold air pressure.   
  • Tubeless Tyres: These do not require inner tubes. Instead, they form an airtight seal with the rim, and a liquid sealant is used to prevent air leakage.  
  • Tubular Tyres: These are less common and are often used in racing. They consist of an inner tube sewn inside a casing, and the entire tyre is then glued onto a special tubular rim.  

The tread pattern on the tyre's surface varies based on the intended use. Different tread patterns provide traction and grip on different terrains, such as slick road surfaces, gravel, or off-road trails. Each of the tyres within the Bike Club fleet of first pedal and hybrid bikes use a versatile multi-terrain tyre, suitable for use on almost all terrains.  


bike gearing - bike club

Gearing systems can vary depending on the type of bike, such as road bikes, mountain bikes, or hybrid bikes. The choice of gearing depends on factors like riding style, terrain, fitness level, and personal preference.    

Gearing refers to the system that allows a cyclist to change the mechanical advantage of the bike's drivetrain. This enables them to pedal comfortably and efficiently at different speeds and on various terrains. Gearing consists of several components:   

  • Chainrings: These are toothed discs attached to the crankset (as above). They come in different sizes, typically denoted by the number of teeth. The front chainrings, in combination with the cassette or freewheel, determine the bike's gear range.  
  • Rear Cogs: (Cassette or Freewheel): Rear cogs are the toothed gears attached to the rear wheel hub. They are available in a range of sizes and are commonly referred to as the cassette in modern bikes. In some designs, they may have a different mechanism called a freewheel. Freewheels come as a whole unit that screw on, whereas cassettes slot onto a freehub and have some sprockets as separate parts. Cassettes are much lighter and longer lasting.
  • DerailleursThe mechanisms responsible for moving the chain between different chainrings and rear cogs. The front derailleur controls the chain's movement between the front chainrings (rarely seen on modern lightweight kids bikes), while the rear derailleur shifts the chain across the rear cogs.  

Gearing provides a range of gear ratios, which represent the relationship between the number of teeth on the chainrings and rear cogs. A higher gear ratio offers a larger mechanical advantage. It means harder pedalling, but a greater distance travelled for each rotation of the cranks compared to a lower gear ratio.  

The gear range refers to the span of gear ratios available on a bicycle. A wide gear range encompasses both high and low gears. This allows riders to tackle steep climbs and achieve faster speeds on flat terrain.  

Questions We Get Asked About Kids Bikes Components

Are adjustable handlebars and stems important for a growing child?  

Yes, but more important is selecting the optimum size bike in the first place. If changes to the bar or stem are required, therefore changing the stack and reach of the bike, this suggests the child has outgrown their bike and is ready to exchange.

Can I add stabilisers to any kids' bike?  

While stabilisers can be added to many kids' bikes, we highly recommend starting with a balance bike. Balance bikes help children develop essential skills like balance and coordination, making the transition to a pedal bike smoother. Additionally, some kids' bikes, like the Woom 2 that we supply, cannot fit stabilisers due to its chain guard. These bikes are specifically crafted to support children in developing balance and cycling skills naturally.  

How do I choose the right saddle size for my child?  

Selecting the right saddle size for your child is generally not a significant concern for the majority of kids. We offer bikes from reputable brands like Frog, Woom, Forme, whose bikes come with well-fitting saddles.  

These companies have carefully designed their bikes to ensure proper fit and comfort for children. We have a blog on children's bike sizes to help you make a choice.

As long as you choose a size-appropriate bike, you can trust that the saddle will be suitable. 

How often should I perform maintenance on my child's bike components?  

Performing regular maintenance on your child's bike components is essential to ensure their safety and prolong the lifespan of the bike. The frequency of maintenance depends on factors such as usage, riding conditions, and the age of the bike.

As a general guideline, it is recommended to perform a basic inspection before each ride and a thorough maintenance check every few months. This includes checking tire pressure, inspecting brakes and cables, ensuring proper chain lubrication, and examining the overall condition of the bike. 

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