Mount a Bike Tyre With a Wire Bead

pump a small amount of air into the tube so it holds a circular shape and is roughly the same size as the folding bike tyre.

It's good practice to mark any coloured label or script at the valve hole. This may make it easier to trace a small elusive puncture hole. If the wire bead bike tyre doesn't have a label use the pressure information or some other identifiable marking.

Fit one bead onto the rim by getting a section into the well of the rim -- the bottom of the rim nearest the centre of the wheel -- to generate enough slack to get the rest over the rim wall. The tyre is half on.

Feed the tube into the wire bead tyre with the valve adjacent to the label.

Put the wheel on the floor with the valve at the bottom and the open side of the tyre away from your legs. Place your hands together on top of the tyre with your thumbs on the side away from your legs. Point your thumbs away from each other.

Push the first section of bead over the rim. Lock one hand in position and work the other away rolling the tyre bead over the rim wall. Once your hand is halfway down lock it and work the other in the opposite direction until it's also halfway to the floor.

Once you've reached the point where the tyre will stay in position on the rim deflate the tube. Hold the valve open(link) while you force the wheel against the ground to force as much air as possible out. The air holds everything together so it also makes the next step more difficult.

Go back to the start position with thumbs pointing away from each other. Squeeze the beads together and force them down into the well of the rim. Slide your hands apart keeping the tyre in tension so the length of tyre above your hands follows the shortest path available. You don't need to stretch the tyre just hold it in exactly the right position.

As your hands reach the three o'clock/nine o'clock position you can lean on the tyre to hold the beads in place. Get your thumbs to the point where the bead is going over the wall of the rim. Work the bead over the rim with your thumbs as you keep the tyre in tension to concentrate the slack at the area around the valve. Use this slack to roll the last section over the rim.

Press the valve up into the tyre to check the valve seat is inside the beads. If not the beads will lift off the rim when you press the valve. If the valve seat is trapped wiggle the valve to force the valve-seat though the tyre beads. If you don't do this the air going in to the tube will force the tyre off the rim, instead of locking the tyre on to the rim.

Inflate the tube to about 25psi or 1.5BAR work round both sides of the tyre, in turn, forcing the bead away from the rim to check the tube isn't visible. If you can see the tube it's trapped under the bead.