Buying a bike which is the right size is probably the most important part of choosing your new cycle. But how do you work out what size to get? A good shop should be able to advise you and let you try different sizes, but there are a few guidelines which help:
12" Wheel Cycles - Suitable for ages 2½ to 4
14" Wheel Cycles - Suitable for ages 3 to 5
16" Wheel Cycles - Suitable for ages 5 to 7
20" Wheel Cycles - Suitable for ages 7 to 9
24" Wheel Cycles - Suitable for ages 9 to 11
26"+ Wheel Cycles - Suitable for ages 11+ (These are classed as adult cycles.)
Once you are into 26" wheel bicycles (road bikes have 700c wheels), then size is only determined by Frame Size. The size of the frame is measured from the top of the frame at the point where the seat post is inserted, down to the centre of the axle carrying the pedal arms (bottom bracket). In the UK and USA this is measured in inches, in Europe it is often in centimetres. Unfortunately some manufacturers measure their models to the centre of the intersection of the top tube and the seat tube, which can throw some of the sizings out a little. If in doubt, ask the shop and they should be able to tell you which way a particular bike is measured - or bring a tape measure!
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