3-speed bikes have already been used since the early 1900s for various purposes – delivering mails and small packages, commuting, and racing, among others. Today, they are still widely used for commuting and other functions over bicycles with the usual derailleur systems.
You can already tell a 3-speed from other bicycles just by looking at it. You'll notice only one sprocket attached on each end of the chain. Derailleur bikes have sprocket clusters, each of which can be moved to an adjunct sprocket to change gears.
A 3-speed utilizes internal hub gears to provide the needed three gear ratios. Internal hub gears are a modern geared technology where the gear is fully enclosed within the rear hub of the bicycle. When riding in middle gear, the rear sprocket and the wheel turn at the same speed. Put it in low gear and the rear sprocket will turn faster than the wheel. Shift to high gear and the rear wheel will turn faster than the sprocket. The sprocket is the metal disk that's built with teeth that makes the chain move. On 3-speed bikes, the front sprocket is larger than the rear one, so the rear sprocket spins more than the front.
So how do you use the gear lifts on a bike? Generally, you shift to a lower gear when going uphill or when pedaling seems difficult and to a higher gear when going downhill or when pedaling is easy. When you feel as if you're pushing the pedals too hard and you're still going slowly, you take the first gear. Shifting to a lower gear will make you run a shorter distance with pedal. On the other hand, when you feel like there's no resistance involved in pedaling, shift to a higher gear, which takes you farther every time you pedal.
Aside from daily commuting and running errands, 3-speed bikes are also used by many people across the globe as an effective equipment for weight loss training. This type of bike would be enough to take you on a daily cycling routine at a reasonable exercise pace of about 12 to 14 mph.
While there are bikes today that are equipped with 27 gears, a 3-speed is usually enough if you're living in a reliably flat region or an area with slight slopes. If you think that you need your low gear to be lower or your high gear to be higher, you can simply go to a bike shop and have them adjust your front or rear rings so you can have the gear range you want.
Source by Candy Carr