If you've bought a bike by mailorder or over the internet then you'll be assembling it yourself. Good firms will do all the hard work for you, which means the brakes and gears should be set and ready to go. If this isn't the case, we've got a handy 'how-to' video below, which shows the whole bike build process. But it still pays to carry out a few checks to ensure the bike is safe to ride.
Here's our guide to getting you up and running. If you're in any doubt of your mechanical skill, it may be better to see if a shop will do it for you. However, they'll be busy at this time of year and some may not take too kindly to assembling a bike that wasn't bought from them.
Time: 1-2 hours
Tools: 4, 5, 6, 8mm Allen keys, 15mm pedal spanner, anti-seize grease
Step 1: Wheels
Insert the wheels into the frame and forks. On mountain bikes with disc brakes, make sure the disc goes between the pads at the calliper.
Make sure the quick-release skewers are tight, especially at the front. The quick-release should be done up so there's a strong resistance to the lever when you close it. Ensure the lever is tucked in against the frame and fork leg, not sticking out.
Step 2: Seatpost
Remove the seatclamp bolt or quick-release and smear grease on its threads before refitting. Smear some grease on the seatpost too and fit it in the frame. Line up the saddle with the top tube of the frame and tighten the seatclamp bolt.
Step 3: Saddle
As a starting point, check that the saddle is level. If not, adjust it by loosening the bolt at the top of the seatpost. Even with the best micro-adjust seatposts, you may need to make a couple of attempts before it is correct.
Step 4: Pedals
Check that you are fitting the correct pedal to the crank. Most are marked with either L or G for left and R or D for right. Smear some grease over the threads before refitting to the cranks. Screw the first few threads in by hand in the same direction that the crank turns when pedalling. For the right-hand (chainwheel side) pedal, turn the spindle clockwise. For the left-hand pedal, turn the spindle anti-clockwise.
Step 5: Brakes
Check that the brakes are correctly set up and everything is tight. Pads on rim brakes should not rub the tyre and should be correctly aligned to the rim. Squeeze the brake levers hard to make sure everything works.
On disc brakes check the callipers are correctly aligned to the disks and tight. Adjust the brake levers on the bars to the right position.
Step 6: Headset and tyres
Check that the forks rotate freely and without play - if not, adjust the headset. Loosen the stem/steerer clamp bolts. Loosen the top cap bolt off and then retighten until all play is removed from the headset whilst ensuring that the forks still rotate easily. Take care to get this adjustment correct. Align the stem with the forks and tighten the bolts that clamp it to the steerer tube. Pump up your tyres to the correct pressure and you should be ready to ride.