How to Build a Child's Bike



Halfords will build your bike ready to ride for just £10 (free for bikes over £250). However, if you’re handy with a spanner and want to build it yourself, here’s our essential guide.

In this article, we describe how to build a child's bike safely, including the essential safety checks you’ll need to perform before the bike is ready for the ride.

What you'll need

If you have opted to buy a boxed bike, before you start unpacking it, ensure you’ve got all the tools you’ll need to complete the job.

To build a child’s bike you will need:

  • Hex key set
  • Socket Set
  • Grease
  • Safety gloves
  • Tyre pump
  • Spanners
  • Pedal Spanner

If you’ve got a bike stand already, then it can make building a kid’s bike easier, but it’s not essential.

Before you start building, unpack everything and check that you have all the parts you need. Open all plastic bags and lay the parts out on the floor somewhere easily accessible. Trust us, opening plastic bags in greasy gloves is fiddly and frustrating! Check for any parts that may need fitting during the build process. You may have to install mudguards, stabilisers, basket or even a doll carrier as you go along.

Fit the seat post

Start by greasing the seat post and slide it into the seat tube. The grease makes it easy to slide the seat post up and down when you need to adjust it and stops it from seizing in place.

Don't worry about getting the height for your little one exactly right just yet; you can set it later. At this stage, you just need to slide it in place and tighten the bolt up where it meets the bikes seat tube to hold in in place.

Fit the front wheel

Check the direction of the tyres, (this is usually written on the tyre side wall with an arrow along with some other tyre specific details) and then slide the wheel into place. This should be nice and easy if the tyres are still deflated as it will slide in-between the brake pads on the front brake calliper.

Using the correct size spanner for the wheel nuts ensure that the safety washers are in place, make sure the wheel sits in tight to the bottom of the fork keep it upright with equal clearance of the tyre from the forks on either side, Tighten the wheel nuts until it is safe and secure. Give it a shake to make sure it is secured before moving on to the next step.

Fit the handlebars and stem

Slide the handlebars into the fork tube and tighten up the bolts using a hex key or a spanner as required.

You’ll want to ensure the handlebars are on straight, so stand over them and look down. Make any adjustments you need and secure them in place. Check that all the cables are seated in the right place ideally down the front of the handle bars making sure they are not twisted and turn the handlebars both ways to ensure they move freely.

Inflate the tyres

Use the pump to inflate the tyres. Check the sidewall of the tyre for guidance on the right air pressure. Under- or over-inflating your tyres can be dangerous, so stick to the recommended pressures.

Use the pump to inflate the tyres. Check the sidewall of the tyre for guidance on the right air pressure. Under- or over-inflating your tyres can be dangerous, so stick to the recommended pressures.

Fit the pedals

The left and right pedals might look the same, but it’s crucial you get the right one for each crank arm as the threads are different. If you try and fit the wrong pedal, you could strip the thread on the pedal or crank, causing extensive damage.

Once you are sure you have the correct pedal for both sides by checking for either a sticker or and L or R embossed into the pedal thread arms, grease the threads, and use a pedal spanner to tighten them. Check they are tight with your hands, and you are good to go.

Safety checks

Before letting your little one ride their new bike, you should ensure everything is working safely and smoothly.

Press and release the brake levers to check they are working and slowing the wheel down to a stop. Check the back wheel rotates freely and the chain is smooth by lifting the back of the bike up and turning the pedals a few times.

Check the brake pads are tight in the calliper and not catching on the wheel or squeaking, if they are they may need a small adjustment to move the pads, just so they are flat with the wheel braking surface. You may need to make a tiny adjustment with a correct sized spanner to loosen off the nut on the rear of the pad readjust and re tighten. Finally check that the front-wheel turns freely by lifting it off the ground and giving it a few spins.

Check that the seat post, handlebars, pedals, and accessories are all secure in place. When turning the pedals listen out for any nasty noises and feel for any resistance or rubbing.

Check that the seat post, handlebars, pedals, and accessories are all secure in place. When turning the pedals listen out for any nasty noises and feel for any resistance or rubbing.

Before setting off, check the chain is in good condition and add a little lubricant if it looks or feels dry.

Older Childrens Bikes

For older children's bikes they may have gears or Disc Brakes (usually bikes 18” or above) so you may need to check the gears to ensure they are set up right and change into the right gear when selected, and you may need to ensure the disc are not rubbing on the pads and the wheel runs smoothly.

Fit accessories

Once the mechanicals are done, it's time to fit the bling!

Accessories enable your child to personalise their bike, with extras such as ribbon streamers, horns, reflectors, and bags all adding some style. Tighten up the bell, give it a ding and you are ready to go!

Need some help building your child’s bike?

Building a children's bike isn't a particularly difficult task, but it does take some time, some planning and the right tools.

Spend £250 or more on your child's bike from Halfords and our expert technicians build it for free. Or for just £10 if you spend less. Alternatively, if you need some help assembling your new child's bike that has been purchased from another non-Halfords store then drop into your nearest Halfords store where someone will be able to help for a small fee. Learn more!

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