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ANALYSIS OF MECHANISMS
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Choosing the right size bicycle
It is important to choose the right size bicycle, so you can ride it properly and avoid problems
or injuries. Look at the chart to see the correct size for you.
Check the size of your own bicycle. Stand next to the seat with your left foot on the
ground. Then lift your right knee upwards and forwards. The space between your knee
and the handlebars should be about the width of your hand.
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Adjusting the seat
Your legs should be almost fully extended when you are pedalling your bicycle and your
feet come closest to the ground. This will help you to avoid knee injuries. To adjust your
bicycle properly, you should:
1.
Ask someone to help you get on the bicycle.
2.
Put the heel of your foot on the pedal and extend your leg completely.
3.
Adjust the seat at that height. When you pedal with your toes, your leg will not be
completely extended.
4.
Notice how you sit on the seat. If you are sitting too far backward, the seat is too
low. If you are sitting too far forward, the seat is too high.
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Taking off the wheels
In some situations, you will need to remove the front wheel of your bicycle. For example,
you might need to change the tyres or the inner tube. Follow these steps:
1.
Disconnect the brake system. If you have a disc system, don’t use the handle after
you remove the front wheel.
2.
Loosen the nuts on the front axle. Hold the nut on one side in place while you turn
Basic operations with your bicycle
Bicycle sizes by crossbar
height
Height (cm)
Size
71-7
73-74
75-78
79-82
83-84
85-88
89-90
91-92
93-94
15
15.5
16
17
17.5
18
19
19.5
20
the nut on the other side. If your front wheel has got a quick release system, simply turn the lever.
3.
Lift the front of the bicycle and the front wheel should fall out.
4.
If you need to remove the back wheel, select the highest gear, so the chain will be on the smallest sprocket. Then
remove the chain and take off the back wheel.
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Changing an inner tube
1.
Deflate the inner tube completely.
2.
Lift up one edge of the tyre, starting with the valve, using tyre levers.
3.
Leave the tyre on the rim and remove the inner tube.
4.
Check the rim and the tyre for any sharp objects.
5.
Partially inflate the new inner tube and put it inside the tyre. Start with the valve.
6.
Put the tyre back on the rim.
7.
Make sure the valve is in the correct position. Inflate the inner tube and then put the wheel back on the bicycle.
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Rethreading the chain
If you need to put the chain back onto the chain wheels, follow these steps:
1.
Put the chain on the lower part of the smallest sprocket.
2.
Lift the back wheel and pedal backward. Thread the chain onto the sprocket.
3.
Pedal forward until the chain is completely connected to the gear wheel.
ADVANCE EDITION
