How to build a bike

If you have bought your bike online, then it will need to be put together. You will need some tools, time and patience.  Follow our guide on how to build a bike and you’ll be able to be riding that new bike and not just looking at a cardboard box.

Tools required

• Bike stand- The bike can be put together without one but some tasks like gear adjustments can be difficult.
• Set of allen keys- Most of the bolts on the bike and some pedals use allen keys.
• Set of metric spanners– Some budget bikes use hex nuts and bolts to secure the wheels, saddle and seatpost. 
• 14mm socket- Might be useful when tightening some crank bolts. Some sockets are too wide so check the one that you have fits.  There are specialist bike tools for this.
• Grease- Used on bolt threads and pedals. NOT on the chain!
• 15mm/pedal spanner- A pedal spanner is the best tool for the job as it is slimmer than other spanners for a better fit and case hardened to stop it slipping.
• Scissors/utility knife- Useful for removing packaging. 
• Phillips screwdriver- Used for fitting accessories.
• Torque wrench- Used to set the correct bolt tightness. Essential tool for carbon and lightweight aluminium components.
• Pump- Used to inflate tyres.

How to build a bike step by step

• Have a look at the box. The inspection holes should be at the top and there might be other information such as where the front and back of the bike is and where to open it. 

• Open the box. Check for any staples and remove them if necessary to avoid damaging the bike or cutting yourself.

• Stand in front of the box, grab the rear wheel with one hand and the frame with the other and lift it out of the box.

• Stand the bike on the floor.
• Remove the accessories box and check for any other loose items.
• Open the accessory box and check the contents.

• Put the bike box aside, don’t throw it away yet in case you might need to return the bike. 

• Cut the zip ties or string that are securing the front wheel and seat post. Do it carefully making sure you don’t cut the gear or brake cables or damage the tyres or the frame. 

• Remove the front wheel and saddle and seatpost and put them aside.

• Remove all the packaging from and around the headtube.

• Cut the zip ties or string and release the handlebars from the frame.  

• If the stem and handlebars are already assembled, they need to be attached to the fork. 

How to build a bike- Attaching the stem and bars. (Quill stem.)

• First remove the plastic sleeve. 

• Twist the stem and handlebars so that the cables are not tangled. 

• Add some grease to the bottom of the stem.

• Fit the stem so that the minimum insertion mark is no longer visible and the stem is facing forward. 

• Set the handlebars to the correct position and tighten the bolt on the top of the quill stem. 

How to build a bike- Attaching the stem and bars. (Threadless stem)

Undo and remove the top cap and the bolt.

• Remove the cardboard or the plastic sleeve/spacer.

• Move the spacers and the stem to your desired position.

• Grease the bolt.

• Replace the top cap.

• Tighten the top cap bolt, but not too much as you could compress the headset bearings.
• Align the stem and tighten the bolts on the side. If there are two bolts then tighten each one alternately a little at a time. 

• Do the final tighten. To make sure it’s the correct tightness without a torque wrench, insert the allen key and use two fingers on the end and push as hard as you can.

How to build a bike– If the stem is already attached to the bike.

• Undo the stem plate bolts and remove the plate. 

• Grease the stem plate bolts and put the plate in easy reach. 

• Now grasp the handlebars and twist them so that the cables are not tangled. 
• Place the bar on the stem so that the gear indicators are at the top and the brake levers are facing forward. 

• Fit the stem plate and tighten the bolts. Watch our video here if you don’t know how to do this.

How to build a bike– Fitting the seatpost and saddle.

The saddle is normally fitted to the seatpost.

• Remove the packaging from the seat post. 
• Grease the seatpost.

• Slide it in the seat tube. 

• Tighten the seatpost clamp. 

How to build a bike–Fitting the front wheel and pedals.

• Put some cardboard or rags on the floor, grasp the seat tube with one hand and the fork with the other and turn the bike upside down.

• Remove the packaging from the front wheel and forks.

• If the bike has rim brakes make sure that the caliper is open.

• Fit the front wheel. Watch this video on How To Put A Front Wheel On A Bike if you need a help with the task.

• Remove the packaging from the cranks.

• Apply a small amount of grease to the pedal threads.

• Fit them into the cranks. The right hand pedal screws in clockwise and the left hand anticlockwise.

Our video here will help you to fit pedals correcty.

How to build a bike- Pump the tyres. 

Watch our video here if you are not sure how to pump the tyres.

How to build a bike- Find and record the frame number. 

The frame number is usually under the bottom bracket shell or sometimes on the seat tube.

It is a unique number and is worth recording because it can be used to prove the bike is yours.

How to build a bike– Adjustments.

Grasp the seat tube in one hand and the fork blade in the other and flip the bike over.

Remove all the packaging including any plastic guards. 

Adjust the saddle, stem and handlebars. Our video here will help you with this task.

Check that all the bolts are tight. If you have a torque wrench, tighten to the correct torque. Some components might have the torque imprinted on them. If you need the correct torque for the rest of the bolts click the link below this video where you can find the full list.

How to build a bike– Accessories.

Fit the reflectors and the bell. The white reflector goes at the front and the red at the back. The bell can go on either side.

You may also need to fit the front mudguard if the bike comes with fenders.

Adjusting brakes and gears

Check and adjust the brakes if required. Our video here will guide you through this process.

If you have a bike stand, put the bike on it.

Check the gears and adjust them if necessary. Watch this video for the correct procedure.

…And finally.

Remove the bike from the stand. Test ride the bike and further adjust if necessary.