How to build a new bike from a box

It is very important to have your new bicycle built/set-up correctly, for safety reasons, for brakes and gears to work correctly/smoothly and to give you years of enjoyment. Many bicycles are now brought on the Internet and are delivered in a box.
Cycle Tech recommends your new bicycle is assembled by an expert to British Standards 6102 Part 1, 1992.

Bike in a box.
Pre-delivery inspection (PDI) Bike in a box build
Time 1 hour


Tools you will need to build your new bike from a box:

Track pump
15mm Pedal Spanner
Philips and flat screwdrivers (Gear & brake adjustments)
5mm Allan key (Depending on make & model Allen keys 3, 4, 5 & 6mm may be used)
Wire cutters (To cut brake, gear cables and to crimp ends)
Spoke key (Too true buckled wheels)
Can of lubricant & grease (Wet-lube To lubricate brake & gear cables)
Workshop stand (optional)

New bike build:

Remove the bike from the box carefully and remove packaging. Fit seat post and clamp the bike in the workshop bike stand.

Front wheel:

Fit quick release skewer to the wheel, first apply a thin layer of grease along the entire length of the skewer rod. Check the rotation of the tyre (Arrow marking on the sidewall of tyre rotating forward) and the quick release skewer lever is fitted to the left side of the bike.

When installing the front wheel, simply place the axle evenly up into the fork dropouts, with the quick release lever on the left side of your bike. Making sure the wheel is aligned central between the forks. Holding the cap with one hand, spin the lever clockwise, making sure the side marked ‘Open’ is facing outwards. When tightening the lever, it should meet resistance at about the halfway point. Now push the lever closed. The leave should be pointing up in the locked position.

You will need to identify the Left and Right pedal, if fitted incorrectly can permanently damage the crank arm threads.

(R) Right hand threaded pedal (The threads are pointing to the right) This pedal fits the right-hand crank arm/the right-side of the bicycle and screws clockwise to tighten up.
(L) Left hand threaded pedal (The threads are pointing to the left) This pedal fits the left-hand crank arm/the left-side of the bicycle and screws anticlockwise to tighten up.

Put a little grease on the threads. Start by hand and tighten with the pedal spanner.

Handlebars and stem:

Grease clamp bolts before fitting handle bars.

Tighten clamp bolts evenly, there should be an even gap between clamp and steam top and bottom.

Check alignment of the steering

Tighten pre-load Aheadset bolt.
The bolt compresses the stem down onto spacers. The preload bolt does not hold the fork onto the bike; after the preload is set, the stem bolts must be tightened to secure the fork in place. The adjustment must be made such that there is no play in the bearings, but allow the fork to turn smoothly without binding or excessive friction.

Align the stem with the front wheel.
Align steering before tightening stem clamp bolts (5Nm)

V brakes.

Adjust brake lever reach for small hands, by screwing the reach adjustment screw-in to bring the brake leaver closer to the handlebars. On this bike the screw is found under the brake leaver.

Fit brake cables to brake levers

Lubricate inner brake & gear cables before sliding in to outer cable.

Fit cables to housing stops.

Over 90% of new bike builds will need the wheels truing and this needs to be done before you can adjust the brakes. The video shows the wheel spinning out of alignment. Watch the gap between rim and brake block. 

Using the spoke key, tighten the spoke on the opposite side to where the rim rubs the brake block 1/2 a turn at a time. (This is best to be done by a expert)

Align brake pads to rim, incorrect alignment can cause inefficient braking and uneven wear to brake pads.

Fit brake cable to V-tube, attach to caliper and pinch bolt adjust cable tension and tighten pinch bolt.

Cut and crimp cable ends.

The video shows  how to center brakes.


Derailleurs need to be set-up correctly to avoid damage, rapid wear and for a smooth gear change.

Rear gear stop screws marked H for high gear & L for low gear.
To adjust: Put the chain in to high gear (smallest sprocket at the rear) and adjust the H screw until the chain is exactly in line with the high gear sprocket.

Rear gear cable adjustment.
To adjust: Put the gear into the second gear in from the smallest sprocket and adjust the gear cable so the derailleur is exactly in line with the sprocket the chain is on. (Turn the cable anticlockwise to move the derailleur to the left)

Adjusting L screw:
Put the gear in to low gear the largest rear sprocket and adjust the L screw so the derailleur is exactly in line with the sprocket the chain is on.

Front gear adjustment screws. Marked H & L

To set-up: Put chain in the low gear on the front chainring (Smallest chainring/inner chainring) and the low gear at the rear (The largest sprocket) Turn the L screw until the inner side of the derailleur touches the chain and then back off the screw 1/2 a turn.
Now put the chain at the front on the middle chainring and adjust the cable so the derailleur just touches the chain.
Put the chain in the highest gears (Smallest at the rear and biggest at the front) and adjust the H screw until the outer side of the derailleur just touches the chain and back off 1/2 a turn.
Check the gears change correctly and the chain does not come off and fine tune if necessary, also carry out a road test.

Front gear cable adjustment at gear shifter


Check valve alignment before pumping tyres.

Look at tyre sidewalls to see tyre pressures. This side wall shows Minimum 50 PSI Maximum 75 PSI

Adjusting bike to rider:

  • Now your bike is built you will need to set-up the saddle height and position.
  • The handlebar and brake levers to the correct position.

You should check your brake and gear adjustments after 4 - 6 weeks as part of a 1st service

Enjoy riding your new bicycle. Martin Cycle Tech UK

No comments:

Post a Comment

Please leave a review to help others and for us to continue to improve our service to you.
you can leave a comment by posting a review of our service and rate your mechanic.