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Repurpose two old bicycles into a bicycle built for two. Tandem buliding is a good buzz.

Great fun can be had when you can explore the world with four-foot power.

Here are the steps from Uncle Afrely's Earth Guide.

1. Two bike frames. A little scratching around the local recycling tip and/or the use of freecycle will achieve this end.

2. The front fork has to be hacksawed off the back frame. The struts between the seat and the back hub have to be removed from the front frame. The back forks are kept apart by a small bar. This may have to be removed on the front frame to bring the forks together for Weld 1. Other obstructions to Weld 2 must be hacked off as you see fit. The back handle-bars may have to be reversed to fit behind the front seat.

3. Welding

Weld 1: Connects back forks on the front frame to the front diagonal tube on the back frame. A clamp or some hammering may be needed to hold the forks on to the tube.

Weld 2: This si the main structural weld and should be done thoroughly. Cleaning off the paint first is helpful.

Weld 3: This makes the back handle-bars immovable. If you don't think this is necessary then we'll let you find out from experience. Some workshops at garages or will weld for you, if you can't find a friend with the necessary techological apparatus.

4. Attaching Pedals

Basically you have to overcome the problems as you encounter them. Problems can be caused by the fact that there are different types of pedal sprockets and associated axles. Since you have to fit two sprockets on the back part you will probably need a long axle even if yo have sprockets of the first type. With a long axle you will need a sprocket of the first type for the left hand (from above) side.

For the front pedals you don't necessarily need to have a long axle. If you do have a long one, you can fit a sprocket of type 1 on the left hand side. If you have a short axle, or a long axle with typr 2 sprocket, you will need to take out the axle and reverse its direction. Much care is needed when taking it out and putting it back in properly - watch the ball-bearing, for if you don't, many problems - like pedals falling off - will occur later.

5. Putting on chains

The back chain is the same as a normal bike. The front left hand side chain will be about 1 1/3 normal chain lengths. The extra chain can be broken down from a normal chain by punching out the connection between links. Then this has to be joined. There are a few combinations of how the links will meet, for example you may end up with (illustration).

'1 1/2' links can overcome some problems. The other problem may be that you have either an impossibly hard chain or a very loose one. Chains can be stretched.

6. Wheels

The extra weight on the wheels of a tandem means an initial investment in new tyres and tubes is worthwhile to avoid monstrous blowouts. The tubes should be inflated hard.

If you have coasting hub with pedal brakes, the cones should be adjusted very well since the hub suffers much more strain than a normal bike.

If you have a geared wheel, either the back person will have to control the gears or you will need to find an extra long gear cable.

If you have hand brakes, either the front rider has no control of the back wheel or you'll have to imrpovise a long brake cable.

7. Painting

The Alfrelymobile was painted green to trick caterpillars. If you paint the wheel rims, sandpaper off any rust first.

8. Problems

Having a girls frame at the back, although convenient, was not strong enough and needed to have a crossbar added.

Pedals falling off, back wheel continually slipping, frame cracking (overcome with a good weld), pedal axles continually loosening and wobbling, and cotter pins wearing out. Most of these were due to the component parts being old.

9. Setting off

Roll up your pants (the left leg on the front and both legs on the back). Hold the handle-bars firmly and set off to see the world with your friend.

If you hear folk saying "look at that", don't bother to see what they are pointing at - it'll be you!

10. A bicycle built for two

"Daisy, Daisy, give me your answer do
I'm half crazy all for the love of you
It won't be a stylish marriage
I can't afford a carriage
But you'll look sweet upon the seat
Of a bicycle built for two".