The two main dimensions on a bicycle are the frame size and wheel size. The frame measurement made from the middle of the bike’s “crankset” (where the pedal arms are attached to) at the bottom center of the bike, upward to a point at or near the top of the seat tube (where the seat post enters he frame.) As a general rule, you can take the riders inseam length minus 12 inches, and that is the size of frame the rider will need. For example, if you have a 30” inseam, take 30” – 12” = 18” frame size. Of course, you can always adjust the seat up and down. If riding on trails, a little bit of a smaller frame may make it easier to handle, and reduces the possibility of landing on the frame in a very uncomfortable position when putting your feet down. The wheel size is the second measurement. Most adult bikes have 26” diameter wheels, BMX bikes have 20” wheels, and children’s bikes can have from 12” to 24” sized wheels.
Bike Gears:
Most bicycles have gears on them, which allow you to adjust the tension and efficiency of your pedaling power. They give you a choice as to how hard or easily you’ll be able to pedal depending upon your age, fitness level, the terrain, topography, wind, and the weather conditions you encounter while riding. For example, in a very low gear, you can pedal very easily, but you will not go very fast because it takes more turns of the pedals to rotate the tire for you. In higher gears, it takes more energy to move the pedals, but the result is that much more distance is covered with each rotation of the pedals. The ability to switch between gears is very convenient and will allow you to exercise better, smarter, and to ride longer and farther. It also allows you to keep a more stable pedal cadence. The gear shifters are conveniently located on the handlebars as part of the grips (grip shifters), or directly in front of the grips (index shifters). The two most popular, and highest quality manufacturers of gears are Shimano and SRAM.
Bike Styles:
Mountain bikes are designed for harder riding, and are made to take a beating. These are able to be ridden on bike trails. Have rugged, stronger components and frames, intended for rougher, off-road riding in rugged terrain, over rocks and logs, but are often used on-road. Mountain bikes have fat, knobby tires for more traction and “cushion,” flatter-profile handlebars for a more leaned-over seating position, very low gears for easier hill climbing. Mountain bikes also have some have suspension systems for greater shock absorption.
Comfort and Hybrid Bikes are designed to give the rider more of an upright riding position and look similar to mountain bikes, but they are not as rugged, nor are they designed for rough riding. These are good for road riding and some light trail riding. Most have a suspension seat post, front suspension and wider seats for more comfort while riding.
Beach Cruisers are designed for comfort and ease of riding. They have larger tires, some have up to 7 speeds and they have an upright riding position as well as big cushy seats. These are great for riding around town, campus or riding on the beach.
BMX Bikes are one-speed bikes that usually have handbrakes. These are all purpose bikes and are also used for riding dirt trails, jumping, and freestyle tricks. They usually have 20” wheels on them.
Bike Frame Materials:
The main three materials used for bike frames are steel, chromoly, and aluminum
Steel (Hi tensile steel) is strong and reliable, but weighs more
Chromoly (Chrome Molybdenum Steel) is strong and reliable. It can have thinner walled frame tubing and still maintain its strength. It is lighter and absorbs road bumps and vibrations well.
Aluminum Frames on average weigh 1 to 2 pounds less than steel. The aluminum frames are stiffer than steel and can feel like a “bumpier” ride.
Bicycle Safety:
Always check and make sure that everything on your bike is secure, and that the tires have adequate air pressure in them. Make sure the seat is the correct height and that the brakes are functioning properly. Always wear a helmet , ride safely and perform basic bicycle maintenance.
