To work out what gear you are using. Count the number of teeth on your chainwheel then multiply by 26.5 (the size of your wheel) then divide the figure by the number of teeth on the cog at the back. The figure you get is your gear size. It's the number of inches that your bike will travel with one full revolution of the pedal. The higher the figure the farther you will go but it will be harder to pedal the lower the figure the less you will travel but it will be easier to pedal.
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