A bicycle’s performance, in both biological and mechanical terms, is extraordinarily efficient. In terms of the amount of energy a person must expend to travel a given distance, investigators have calculated it to be the most efficient self-powered means of transportation. In terms of the ratio of cargo weight a bicycle can carry to total weight, it is also a most efficient means of cargo transportation.
From a mechanical viewpoint, up to 99% of the energy delivered by the rider into the pedals is transmitted to the wheels (clean, lubricated new chain at 400W), although the use of gearing mechanisms reduces this by 1-7% (clean, well-lubricated derailleurs), 4-12% (chain with 3-speed hubs), or 10-20% (shaft drive with 3-speed hubs). The higher efficiencies in each range are achieved at higher power levels and in direct drive (hub gears) or with large driven cogs (derailleurs).
A human being traveling on a bicycle at 16–24 km/h (10–15 mph), using only the power required to walk, is the most energy-efficient means of human transport generally available. Air drag, which increases with the square of speed, requires increasingly higher power outputs relative to speed, power increasing with the cube of speed as power equals force times velocity. A bicycle in which the rider lies in a supine position is referred to as a recumbent bicycle or, if covered in an aerodynamic fairing to achieve very low air drag, as a streamliner.
On firm, flat ground, a 70 kg (150 lb) person requires about 60 watts to walk at 5 km/h (3.1 mph). That same person on a bicycle, on the same ground, with the same power output, can travel at 15 km/h (9.3 mph) using an ordinary bicycle, so in these conditions the energy expenditure of cycling is one-third of walking.
In utility cycling there is a large variation; an elderly person on an upright roadster might do less than 10 km/h (6.2 mph) while a fitter or younger person could easily do twice that on the same bicycle. For cyclists in Copenhagen, the average cycling speed is 15.5 km/h (9.6 mph).
On a racing bicycle, a reasonably fit rider can ride at 40 km/h (25 mph) on flat ground for short periods
Reduction of weight and rotating mass
There has been major corporate competition to lower the weight of racing bikes in order to be faster uphill and accelerating. The UCI sets a limit of 6.8 kg on the minimum weight of bicycles to be used in sanctioned races
The dandy horse, also called Draisienne or laufmaschine, was the first human means of transport to use only two wheels in tandem and was invented by the German Baron Karl von Drais. It is regarded as the modern bicycle’s forerunner; Drais introduced it to the public in Mannheim in summer 1817 and in Paris in 1818. Its rider sat astride a wooden frame supported by two in-line wheels and pushed the vehicle along with his/her feet while steering the front wheel. The 1860s captured the realease of Velocipede or Boneshaker – a two-wheeled bicycle with pedals and cranks on the front wheel. It was known as the bone shaker because the combination of a wood frame and metal tires made for a very uncomfortable ride over cobblestone streets. See what happened next on the list:
1870s—High-wheeled bicycle: One of the first models to be called a ‘bicycle’ (after its two wheels). The high wheel allowed the rider to travel farther with a single rotation of the pedals. Moreover, a metal frame and rubber tires provided a more comfortable ride than the boneshaker.
1885—Rover Safety bicycle: Invented by John Kemp Starely, England; Featured a strong enough metal to make a chain, plus it had two same-sized wheels and a similar frame to today’s bicycles.
1888—Pnuematic tires: Invented by John Boyd Dunlop, Ireland; Develops air-filled tires that provide a smoother ride than the previously used hard-rubber tires.
1920s—Kid’s bicycles become popular.
1940s—Built-in kickstands developed.
1960s—Racing bicycles become popular and feature dropped handlebars, narrow tires, numerous speeds and a lighter frame.
1980—Spurred by mountain biking and extreme sports, mountain bicycles become a popular consumer item and feature sturdier frames, larger wheels and flat handlebars.
1996—Mountain bicycles appear in the Olympics.
It’s a long way from there to now. Seeing how bicycle develops through time, we know to appreciate what we are having to day and how society grows. Let spend some time to be thankful.
Your bike is a mess? We can give you some easily done basic bicycle care steps that’ll rejuvenate most well-ridden two-wheelers. And the same tips can keep a new bike running and looking new for as long as you want.
Pump It Up
Probably, the number one reason bikes fall apart is because people ignore the tires. Here’s what happens: Bicycle tires have very little air in them. And bicycle tubes, which are made of butyl rubber, are porous enough to allow air to seep out.
The result is tires softening over a period of about a week for road bikes and about a month for mountain bikes (though it depends some on tire size).
When the tires get soft, bad things happen. Some folks decide to stop riding the bike because they think they have flat tires and they put off getting the flat fixed because it means loading the bike in the car and dragging it down to the bike shop.
Lube It or Lose It
A bicycle is made up of a bunch of moving metal parts, many of which are meshing with each other. In order to keep these parts from grinding each other to dust as you pedal merrily along, they should be lubricated.
Spinning parts containing bearings, such as the wheels, pedals, bottom bracket (what the crankset is mounted to), and headset (the mechanism that connects the fork to the frame and allows steering), come from the manufacturer packed with grease. About once a year, these components should be dismantled, checked and regreased. But, because special tools are needed and the work is required only occasionally, you may prefer to leave this job to a bike shop mechanic.
Keep It Clean
Mountain bikers, especially those who ride in the mud, should keep a cleaning kit in the corner of the garage ready for use at ride’s end. All that’s needed is a bucket with some sponges and dishwashing detergent and a nearby hose.
When you return from a ride, prop the bike up and spray off the majority of the mud and muck with the hose. It’s crucial to not blast the water sideways at the bike. Doing so may force the water into the pedals, hubs and bottom bracket, which may compromise the grease and bearings inside these components. Instead, spray water only from above and don’t ever direct it toward greased parts.
I tell everyone to store bike(s) inside. It’s the best way to keep them running and looking like new. And it doesn’t take much in the way of space or supplies. The only item needed is a bike hook. These are shaped like question marks and coated with vinyl so as not to scratch the wheel when you hang the bike on the hook.
Install the hook in a stud in a wall or a rafter or beam; anywhere where the bike can hang vertically is fine. I’ve seen bikes stored in stairwells, bathrooms, bedrooms—anyplace you can find dead space is fine. It’s also possible to use two hooks and hang the bike horizontally, one wheel on either hook.
Be a smart and well – equipped cycler. Before you purchase a bicycle, think about the type of cycling you plan to do. Pick and choose from the myriad of options to find the combination of features that best suits you and your goals.
You might be tempted to buy everything available for your bicycle. In the beginning, you may not need a bicycle computer, GPS, and heavy winter gear. As your experience and skill level improve, you can add items to your gear collection.
If you plan on a combination of road and mountain biking, pick a hybrid. Road bikes are for the road and mountain bikes are for off-road use.
The most important part of bicycle shopping is finding the right frame size. A frame that is too small will place unnecessary strain on your joints. A frame that is too large will decrease the level of control you have over your bike. If the frame is not properly fitted to your body, your center of gravity will be greatly compromised.
When choosing your bicycle, pick the best combination of features for the type of cycling you plan to do. For example, don`t put off-road tires on a road bike.
Many road bikes along with mountain bikes include clipless pedals to which special shoes attach, via a cleat, permitting the rider to pull on the pedals as well as push.
The right cycling shoes will support your foot on the pedal. This can reduce cramping and foot fatigue as you ride. The shoe you pick will depend on the type of pedal you plan to use with your bicycle.
Helmets offer essential protection while cycling. Modern designs are sleek and lightweight. There is no longer a question of style when choosing to wear a helmet. Helmets are proven to save lives and prevent life altering injuries from having their full effect. A good helmet will cost you at least US$50 and the best helmets can cost hundreds of dollars.
Dress for the weather. Lightweight, breathable fabrics are excellent for keeping the body cool and dry in warm weather. Moisture-wicking, heat retaining fabrics like fleece are best for winter riding. Gloves, glasses, socks, and extra outer layers are important regardless of season.
In general, fabrics suited for most outdoor sports will be appropriate for cycling. However, avoid loose fitting clothing as these clothes may get caught in your spokes, chain, or handlebars.
Making New Year’s resolutions to save money, get healthy, or cut your carbon footprint in 2015? You could hit all three by simply riding your bike to work. Here are 5 reasons you should consider making it a new habit this year:
Not only does biking have the potential to improve individuals’ health, wealth, and standard of living, but the combination of more cyclists and fewer cars on the road could give the entire country a much-needed boost.
It would make cycling safer for everyone.
Research shows that unlike cars, the more bicycles on the road, the safer it becomes for cyclists.
“It’s a virtuous cycle,” Dr. Julie Hatfield, an injury expert from the University of New South Wales, says. “The likelihood that an individual cyclist will be struck by a motorist falls with increasing rate of bicycling in a community. And the safer cycling is perceived to be, the more people are prepared to cycle.”
It is vastly cheaper than driving.
Due to rising fuel costs and tire upkeep, the cost of owning a car increased nearly 2% in 2012 to $US8,946, according to AAA.
It costs just $US308 per year to keep bikes in shape — nearly 30 times less than cars, according to the
Sierra Club. It says: “If American drivers were to make just one four-mile round trip each week with a bicycle instead of a car, they would save nearly 2 billion gallons of gas. At $US4 per gallon, total savings would be $US7.3 billion a year.”
It’s a free gym on wheels.
On average, bicycle commuters lose 13 pounds in their first year of cycling alone.
“[Bike commuting] can be a very effective cardiovascular benefit,” says Lisa Callahan, MD, of the Hospital for Special Surgery in New York City. “If you’re overweight and start an exercise program, sometimes it’s harder on your joints because you are overweight, so something like swimming or biking that’s not pounding on the joints can be a good thing.”
You won’t miss morning traffic jams.
Americans spend upwards of 25 minutes per day commuting to work and more than $700 per year simply burning fumes in traffic
Cycling could help you get there faster for a lot less.
“Half of the working population in the U.S. commutes five miles or less to work, with bike trips of three to five miles taking less time or the same amount of time as commuting by car,” writes Kiplinger editor Amanda Lilly.
You don’t even have to own a bike.
There’s been a wave of new bike share programs in major cities like Washington, D.C., Boston, Chicago, and Miami, which typically allow riders 30 to 45 minutes of transportation for a small annual fee.
When New York City’s bike share launched in May, annual memberships
cost $US95 — about $US10 less than subway commuters spend per month.