HOW EXERCISE BIKES DEVELOP RESISTANCE

Whether you are talking about an upright exercise bike or a recumbent exercise bike, they all develop resistance employing one of several methods. One of the earliest methods of developing resistance is by applying variable pressure against the stationary bike’s flywheel. This is usually done with a roller pressing against the outer edge of the flywheel, a pair of brake pads squeezing the flywheel or by a brake belt ( often called a friction belt ) being wrapped around the circumference of the flywheel. Modern spinner bikes use the brake pad system or have a pressure pad that presses against the outer edge of the flywheel like the roller did in vintage exercise bikes.

Another early method of developing resistance is through wind resistance. The Schwinn AirDyne bike is an example of a bike the uses this principle. With this system, the flywheel is a fan instead of a solid wheel and the resistance increases with the speed at which the pedals are turned. The drawback is that a bike utilizing this method can not be used with high resistance at slow speeds like other exercise bikes can.

Most high end residential exercise bikes and virtually all commercial exercise bikes, except spin bikes, develop resistance through some form of electrical or magnetic drag or load. Many of the exercise bikes that you find in fitness centers and some home bikes have alternators like those in cars. The resistance is increased or decreased by increasing or decreasing an electrical load put on the bikes alternator by the alternator control board which responds to user input at the bike’s display console.

Another frequently seen method is through the use of magnetism. In less sophisticated bikes, strong permanent magnets are physically brought closer or further away from the flywheel creating more or less drag on it, hence corresponding changes in the bike’s resistance. High end bikes that utilize magnetism to develop resistance, use electromagnets under the control of regulatory circuitry that varies the power to the magnets, thereby affecting the drag on the flywheel.

There are variations of these basic forms of variable resistance used by countless manufactures of exercise bikes, but in all cases, the changes in the resistance developed, are in turn passed on to the exercise bike’s pedals, making it harder or easier for the user to maintain the revolutions per minute ( RPM ).