Disc brakes are more common in mountain bikes, tandems and recumbent bikes than in other types of bikes, as they have increased their performance and have higher weight and complexity. Probably the most famous and widespread of these inventions, adopted far beyond cycling, is Charles Bennett's Bike Web, known as the jock belt. Poverty fighting men in Uganda who transport bananas by bike experiments conducted in Uganda, Tanzania and Sri Lanka on hundreds of households have shown that a bicycle can increase the income of a poor family by up to 35%. They are also good for commuters who need to take their bike by bike in a bus or train for part of their journey, or who do not have a safe place to park their bike at work. Drop handlebars, as they turn forward and down, offer the cyclist best braking power from an aerodynamic “crouched” position, as well as more upright positions where the hands hold the brake lever, the front curves or the upper flat sections for increasingly upright postures. They have all the necessary mounting bolts for loading racks and fenders, and although they still have a trap bar, they usually have a more relaxed frame design, so that the driver is more upright, for greater comfort on long distances for several days at a time. Fitness bicycles have the most advantages of ordinary road bikes - light frames and relatively narrow tires for efficiency on the sidewalk - with a flat or upright handlebars. These models were called safety bicycles, dwarf guards or upright bicycles for their lower seat height and better weight distribution, although without pneumatic tyres, the ride of the small wheel would be much rougher than that of the larger wheel type. The Road Code of many countries reflects these definitions and requires that a bicycle meets certain legal requirements before it can be used on public roads. Maintenance and repair Maintenance of adequate tyre inflation is the most common and troublesome concern for cyclists, and many means and methods are used to maintain pneumatic integrity. Track/Fixed-Gear /Fixed-Gear Bicycles or Fixies are designed for driving on a Velodrome, an oval track specially designed for bicycle racing. Suspension is particularly important for recumbent bikes, as an upright cyclist can stand on the pedals to achieve some of the benefits of suspension, but a recumbent cyclist cannot. They allow riders to sit back and sit back, and many have small front There are tricycles for children and adults; these have three wheels with a large seat. Mountain bikes can be equipped for use as touring or commuter bikes, although they would not be as light or efficient as conventional touring or commuter bikes. Thin, lightweight bicycle tires are particularly susceptible to penetration and subsequent deflation caused by goat heads and other burs, colloquially known as stickers. Some cyclists choose self-service: they maintain their own bikes, perhaps as part of their hobby cycling or simply for economic reasons. Triathlon/time trial races usually have staggered starts in which each racer starts on his own; these bikes may not normally be used in mass starting races. These are naturally more aerodynamic than upright versions, as the rider can lean back on a support and use pedals that are approximately at the same level as the seat. Seats A Selle San Marco saddle for women also vary with driver preference, from the padded ones preferred by short distance riders, to narrower saddles that allow more space for leg swings. Its large, padded seats and upright handlebars provide a comfortable driving position and are best suited for casual driving in the neighborhood or cycling paths, short distance commuting and errands in the city. Mountain bikes usually have a “straight handlebar” or “riserbar” with different sweep reverse and centimeter disadvantages as well as wider widths, which can provide better handling thanks to increased leverage against the wheel. These usually have a gear, but the pedals have to move for the bike to roll bicycles These are smaller bicycles that fold up, which they can bring easier for travel. Economic implications Bicycle manufacturing proved to be a training.