Bicycle brakes may be rim brakes, in which friction pads are compressed against the wheel rims; hub brakes, where the mechanism is contained within the wheel hub, or disc brakes, where pads act on a rotor attached to the hub. Most road bicycles use rim brakes, but some use disk brakes.[49] Disc brakes are more common for mountain bikes, tandems and recumbent bicycles than on other types of bicycles, due to their increased power, coupled with an increased weight and complexity.[50]

Saddles also vary with rider preference, from the cushioned ones favored by short-distance riders to narrower saddles which allow more room for leg swings. Comfort depends on riding position. With comfort bikes and hybrids, cyclists sit high over the seat, their weight directed down onto the saddle, such that a wider and more cushioned saddle is preferable. For racing bikes where the rider is bent over, weight is more evenly distributed between the handlebars and saddle, the hips are flexed, and a narrower and harder saddle is more efficient. Differing saddle designs exist for male and female cyclists, accommodating the genders' differing anatomies and sit bone width measurements, although bikes typically are sold with saddles most appropriate for men. Suspension seat posts and seat springs provide comfort by absorbing shock but can add to the overall weight of the bicycle.
In general, U.S. and European cycle manufacturers used to assemble cycles from their own frames and components made by other companies, although very large companies (such as Raleigh) used to make almost every part of a bicycle (including bottom brackets, axles, etc.) In recent years, those bicycle makers have greatly changed their methods of production. Now, almost none of them produce their own frames.
The release of Garmin’s new Edge 520 Plus GPS bike computer made a big splash in the world of cycling. It was an impressive upgrade, likely a response to increasing competition from the likes of Wahoo. But the Garmin Edge 520 Plus upgrade has caused a little confusion, because it seems to offer the same mapping and navigation capabilities as the more expensive Edge 820 and 1030. We clear up the confusion with two in-depth posts, Garmin Edge 520 vs 520 Plus, and Garmin Edge 1030 vs 820 vs 520 Plus.
Bicycle shall mean (1) every device propelled solely by human power, upon which any person may ride, and having two tandem wheels either of which is more than fourteen inches in diameter or (2) a device with two or three wheels, fully operative pedals for propulsion by human power, and an electric motor with a capacity not exceeding seven hundred fifty watts which produces no more than one brake horsepower and is capable of propelling the bicycle at a maximum design speed of no more than twenty miles per hour on level ground.
This 150mm-travel e-mtb tackles big descents, shines on flowy trails, and provides the boost you need for the trip back. Pedal assist comes from Shimano’s 6.2-pound STePS E8000 motor with a 20mph boost. Shifting is motorized too, with Shimano’s exemplary XT Di2 drivetrain providing the most precise and consistent shifts a mountain bike can have. The fun comes from the E-Core’s 150mm of front and rear travel courtesy of a RockShox Yari fork and Deluxe RT shock. Both can be locked out for long, fire-road type climbs, though on an e-bike that feature feels less necessary.
As the managing editor of Ars Technica, one of my duties is to monitor the daily torrent of news tips and PR emails. The overwhelming majority of them is deleted after a glance, and the news tips and story ideas are passed along to the appropriate writer. Sometimes a product announcement will catch my eye, and I will follow up. Once in a blue moon, I'll say, "please send me one so that I may review it." And that's how I ended up riding an electric bike around the Chicago suburbs for two weeks.
An itinerant wordsmith with a broad constellation of interests, Lydia Chipman has turned iconoclasm into a livelihood of sorts. Bearing the scars and stripes of an uncommon diversity of experience -- with the notable exceptions of joining a religious order or becoming an artist -- she still can’t resist the temptation to learn something new. Lydia holds a master of arts in English from Georgia Southern University, and a bachelor of arts cum laude in integrative studies from Clayton College. Her expertise is in the areas of robotics, electronics, toys, and outdoors and computer equipment.
First off we want to apologize for the longer than normal response time and email backlog as much of our team was busy both in the preparation and attendance at the Taipei Cycle Show this past week. We'll be working hard to catch up on that in the coming days and thank your patience and understanding. To all the dealers, vendors, manufacturers, component partners, and general industry friends we met at the show, what a great time and we look forward to exciting pursuits ahead. 
The Netherlands has a fleet of 18 million bicycles.[77] E-bikes have reached a market share of 10% by 2009, as e-bikes sales quadrupled from 40,000 units to 153,000 between 2006 and 2009,[78] and the electric-powered models represented 25% of the total bicycle sales revenue in that year.[77] By early 2010 one in every eight bicycles sold in the country is electric-powered despite the fact that on average an e-bike is three times more expensive than a regular bicycle.[73][78]
Different gears and ranges of gears are appropriate for different people and styles of cycling. Multi-speed bicycles allow gear selection to suit the circumstances: a cyclist could use a high gear when cycling downhill, a medium gear when cycling on a flat road, and a low gear when cycling uphill. In a lower gear every turn of the pedals leads to fewer rotations of the rear wheel. This allows the energy required to move the same distance to be distributed over more pedal turns, reducing fatigue when riding uphill, with a heavy load, or against strong winds. A higher gear allows a cyclist to make fewer pedal turns to maintain a given speed, but with more effort per turn of the pedals.
The last 8 months we've been wrapping up some long duration testing of Statorade across different hub motor lines and performing experiments confirming its long term stability. These results have us pumped to introduce this motor cooling solution beyond DIY'ers and into wider markets. As an example, have a look at the video we below showing the effect this has on a small direct drive folding bike motor.
The first functioning electric motor was displayed in the early 19th century, though the device constructed by British scientist Michael Faraday did little more than swirl a wire around a magnet when an electric charge was introduced. Still, the concept proved that electricity could do work. Functional electric motors would follow in many forms after that achievement in 1821. Soon scientists and tinkerers around the world, including visionaries such as Nikola Tesla, were experimenting with all manner of electric motors -- some worked with DC power, others with AC. By the end of the century, myriad electric motors had been produced, capable of exerting enough force with enough reliable control that they were practical for use in myriad applications.
One of the items we demonstrated at the show is the new GMAC motor series. This is a powerful clutchless geared hub motor developed over the past 2 years in partnership with MAC motors, using a custom axle with an integrated splined torque arm. Imagine a MAC motor with perfect frame fit for modern bicycles, zero torque transmission on the dropouts, and phenomenal regenerative braking control.

The safety bicycle gave women unprecedented mobility, contributing to their emancipation in Western nations. As bicycles became safer and cheaper, more women had access to the personal freedom that bicycles embodied, and so the bicycle came to symbolize the New Woman of the late 19th century, especially in Britain and the United States.[8][73] The bicycle craze in the 1890s also led to a movement for so-called rational dress, which helped liberate women from corsets and ankle-length skirts and other restrictive garments, substituting the then-shocking bloomers.[8]
An itinerant wordsmith with a broad constellation of interests, Lydia Chipman has turned iconoclasm into a livelihood of sorts. Bearing the scars and stripes of an uncommon diversity of experience -- with the notable exceptions of joining a religious order or becoming an artist -- she still can’t resist the temptation to learn something new. Lydia holds a master of arts in English from Georgia Southern University, and a bachelor of arts cum laude in integrative studies from Clayton College. Her expertise is in the areas of robotics, electronics, toys, and outdoors and computer equipment.
It is important to note that if a vehicle has an electric motor greater than 500 watts and is capable of powering the vehicle when traveling at a speed greater than 32 km/h and it does not have a CMVSS compliance label it cannot be registered unless the owner can prove, by having the vehicle certified by an engineer, that it is safe for operation on NB highways. Also, not all vehicles are suitable for operation on NB highways and it could be that the vehicle in question may not be a motor driven cycle or a bicycle and cannot be operated on the highway at all.
"Electric-assisted bicycle" means a bicycle with two or three wheels, a saddle, fully operative pedals for human propulsion, and an electric motor. The electric-assisted bicycle's electric motor must have a power output of no more than one thousand watts, be incapable of propelling the device at a speed of more than twenty miles per hour on level ground, and be incapable of further increasing the speed of the device when human power alone is used to propel the device beyond twenty miles per hour.[66]
When it comes to electric bikes, consumers have lots of choices.  So finding an electric bike to meet your needs won’t be hard.  Today, we are going to take a deeper look at three of the most popular types of electric bikes on the American market and many of the benefits of owning and using an electric bike.  Each of these ebikes has something different to offer as you will find out below.   So if you are looking to purchase a new electric bike in the near future, you just might want to pay close attention to the information provided...
"Bicycle" means either of the following: (1) A device having two wheels and having at least one saddle or seat for the use of a rider which is propelled by human power. (2) A device having two or three wheels with fully operable pedals and an electric motor of less than 750 watts (one horsepower), whose maximum speed on a paved level surface, when powered solely by such a motor while ridden, is less than 20 miles per hour.[citation needed],

I'm one of the hardcore cyclists at Ars, along with Jay Timmer and his new-as-of-last-fall road bike as well as copyeditor Kerry Staurseth. I love cycling, and it was a major factor in my dropping 120lb over a 12-month period starting in the summer of 2009. My daily rider/errand-runner is a 1998 Gary Fisher Marlin mountain bike. For longer rides, I use my 2009 Trek XO2 cyclecross bike. I've made a few modifications to it, including removing the bumpy cyclecross tires and swapping out the front 46-tooth chainring for a 50-tooth one. I went with a cross bike over a road bike because I'm still a Clydesdale, and I like the slightly longer wheelbase of a cross bike. I've also briefly owned a 2011 Trek Madone 5.9, which I sold not long after I bought it due to severely screwing up my right knee.
You can learn more about the development and axle testing process on this endless-sphere thread. Our ambition is to make this splined axle design into a new standard that we deploy across our entire higher power motor lines to replace axle flats. If you're as excited as us and want to jump right into ordering, we have the first production shipment on hand available in bare motors and complete kits.
The Pivot Shuttle breaks the mold when it comes to e-mountain bikes. This ballsy, carbon-frame bike, with Shimano Di2, has 140mm of rear travel, 150mm up front, and a 150mm dropper post. A Shimano STePS e8000 drive unit, paired with a 500Wh battery, provides 20 mph of pedal assist, so you can skip the lift line when you hit the bike park and zip right to the good stuff. The 27.5-inch wheels are nimble and eat up nearly anything in their path, and the massive 2.8-inch tires have huge knobs that grip the trail like Velcro.
This is a cool eBike fits in your car's trunk or back seat! It's well made. And it only has one rear disc brake, you dont really need the front brake. It's simple to operate and fun to use - just put one foot on one foot attachment while turning the throttle slightly, then as soon as you start to move add the other foot...and let the joy ride begin!
The other is our first foray into the larger 45mm wide motor series, similar to those sold by MXUS, QS, Leafbike etc. as 3KW or 5kW hubs. We got these made up to properly fit either a standard 135mm dropout with a single speed freewheel, or a 150mm dropout with a 7-8 speed freewheel and some spacers. As expected from Grin they are sealed, include a 10K thermistor for temperature sensing, and have a disk hole injection port for Statorade, and are hubsink compatible. Check out the performance on our simulator both with and without statorade. Unlike so many other direct drive motors, both of these have the proper alignment for disk rotor position and room for disk calipers without shimming things out.
We rode the Vado through the gauntlet, including some of the steepest hills in Palo Alto, and it easily handled everything we threw at it, maintaining a steady 20 miles per hour even on the most daunting of ascents. The bike also handles well on downhills and is both nimble and quick on city streets and paved trails. It’s even comfortable to ride for extended distances, which is vitally important for any bike built for urban settings.
DIY Kit ebikes – Ebikes that are home built with a DIY kit, and exceed the 750W/20mph definition, are also allowed to be bought, build, and ridden. DIY kits are throttle activated. Some of the newer systems have PAS options. Ebike kits are not unilaterally prohibited or assigned motor vehicle status, but again, legal classification and road use falls under state law.
As electric bike options continue to expand, more brands are integrating the battery more seamlessly. That makes them look sleeker (and more like a real bike). Batteries are expensive, so make sure there’s a good way to lock the battery to your bike if you’ll be keeping it outside. Overall weight is important. Some battery and motors can add 15 pounds or more to the bike. With assist, you won’t feel that much when you’re riding, but you will if you have to carry your bike up stairs or lift it onto a bike rack.
Even with cheaper or heavier bikes, once you accept that you are really meant to pedal gently and let the motor do the work, non-speed freaks will get into it. E-bikes are great for commuting and for places that aren't pancake flat. They'll pull you away from the lights quickly, iron out hills and stop you getting sweaty, so you can bin the Lycra and ride in jeans, a suit, or a winter coat.
Built around a heavy-duty alloy frame, the GSD eschews many of the traits of other cargo bikes: long wheelbases, bigger wheels, and especially, an unwieldy ride. Yet it boasts an extensive capacity, nimble handling—even fully loaded, thanks to a short wheelbase and 20-inch wheels—and enduring range in a package not much bigger than most non-cargo e-bikes. The stout frame holds a 250-watt Bosch motor that gives up to 275 percent of your power back to the pedals and reaches 20 mph. The GSD has room for two battery packs, extending the batteries’ combined range to a claimed 150 miles and making the Tern one of the longest-lasting e-bikes on the market. A laundry list of accessories and a (claimed) 396-pound carrying capacity round out the GSD’s status as an epic day-tripper.
Maintenance of adequate tire inflation is the most frequent and troublesome concern for cyclists and many means and methods are employed to preserve pneumatic integrity. Thicker tires, thicker tubes, tire liners (of a number of rather impenetrable devices installed between the tire and tube), liquid sealing compounds squeezed into the tube, and automotive-style patch kits are all used to reliably contain the typical tire pressures of 40 to 60 pounds per square inch that are required for bicycle operation. Thin, light bicycle tires are particularly vulnerable to penetration and subsequent deflation caused by goat's heads and other burs, colloquially known as stickers. Inflation of bicycle tires to pressures higher than typical for automotive use requires special pumps. The complexity of bicycle tire maintenance and repair may cause many to not consider the bicycle for transport or leisure.
The batteries are the most important parts of the bike, because (if you don't do any pedaling) they contain all the power that will drive you along. Typical electric bike batteries make about 350–500 W of power (that's about 35–50 volts and 10 amps), which is about a quarter as much as you need to drive an electric toaster. In theory, you could use any kind of battery on a bicycle. In practice, however, you want to use something that stores lots of power without being too heavy—or you'll be using half your power just moving the battery along! That tends to rule out heavy lead-acid batteries like the ones that start cars, though some electric bikes do use them. Lightweight lithium-ion batteries, similar to those used in laptop computers, mobile (cellular) phones, and MP3 players, are now the most popular choice, though they're more expensive than older rechargeable battery technologies such as nickel-cadmium ("nicad"). Typical batteries will give your bicycle a range of 10–40 miles between charges (depending on the terrain) and a top speed of 10–20 mph (which is about the maximum most countries allow for these vehicles by law). You can extend the range by pedaling or free-wheeling some of the time.
The dwarf ordinary addressed some of these faults by reducing the front wheel diameter and setting the seat further back. This, in turn, required gearing—effected in a variety of ways—to efficiently use pedal power. Having to both pedal and steer via the front wheel remained a problem. Englishman J.K. Starley (nephew of James Starley), J.H. Lawson, and Shergold solved this problem by introducing the chain drive (originated by the unsuccessful "bicyclette" of Englishman Henry Lawson),[25] connecting the frame-mounted cranks to the rear wheel. These models were known as safety bicycles, dwarf safeties, or upright bicycles for their lower seat height and better weight distribution, although without pneumatic tires the ride of the smaller-wheeled bicycle would be much rougher than that of the larger-wheeled variety. Starley's 1885 Rover, manufactured in Coventry[26] is usually described as the first recognizably modern bicycle.[27] Soon the seat tube was added, creating the modern bike's double-triangle diamond frame.
One of the items we demonstrated at the show is the new GMAC motor series. This is a powerful clutchless geared hub motor developed over the past 2 years in partnership with MAC motors, using a custom axle with an integrated splined torque arm. Imagine a MAC motor with perfect frame fit for modern bicycles, zero torque transmission on the dropouts, and phenomenal regenerative braking control.
The other shout-out goes to Paul Bogaert who decided to close the Bike Doctor after 27 years and instead cycle tour the world with his wife. Paul had an early role in Vancouver bicycle advocacy and at bringing cycle riding to a less elitist/athletic and more everyday commuter crowd through their shop.  They were among the early shops to embrace family friendly cargo bikes and  appreciated the role that electric would play in making cycling more broadly appealing.
Thanks for your feedback Joe! I personally find black on white to be high contrast and abrasive. Instead, this dark gray scheme is meant to be relaxing… but if it’s uncomfortable to you or difficult to read there are ways to change your browser and even your operating system to be more comfortable using the accessibility options. Here’s a list by device type and for some browsers hope it helps!
^ Consumer Product Safety Act, Pub. L. 107–319, December 4, 2002; codified at 15 U.S.C. 2085(b): The CPSC regulations do not differentiate between commercially manufactured low speed electric bicycles and those converted from ordinary bicycles by their owners using an aftermarket electric motor and battery kit, nor do they regulate the construction of electric-power bicycles using owner-built or sourced components.

To operate a motorized/electric-assisted bicycle on the streets or highways a person must have a valid driver’s license or a motorized bicycle permit. A person under the age of 16 operating a motorized/electric-assisted bicycle under a motorized bicycle permit is subject to restrictions of no passengers (a parent or guardian my ride if the motorized/electric assisted bicycle is equipped with a seat and footrests for a passenger), no night driving, driving on any highway marked as an interstate, must wear a helmet, foot rests for passengers (if designed for passenger(s). A motorized bicycle permit is available to persons of at least 15 years of age who have passed the motorized bicycle test or passed a motorized bicycle course. A motorized bicycle would need the same coverage as a motorcycle would in this state. An electric-assisted bicycle would not need coverage.