Conversion kits, on the other hand, are sold and installed separately on traditional bicycles. They are harder to setup and conceal, and require some basic mechanical ability and a little bit of ‘elbow grease’ to install. The advantage of conversion kits is that you can choose almost any standard bicycle, and you have the freedom to change or upgrade components as you go. A conversion kit will also allow you to achieve higher power and speed ratings that are not possible on most pre-built electric bike models. Kits are great for tall or heavy riders because they can opt for a larger bike, with higher power and weight carrying capacity. People living in hilly terrain may require the additional torque to handle extremely large inclines. For people who prefer a specific bike model or just love to go faster, a conversion kit offers enormous flexibility.

There are specialized bicycle tools for use both in the shop and on the road. Many cyclists carry tool kits. These may include a tire patch kit (which, in turn, may contain any combination of a hand pump or CO2 Pump, tire levers, spare tubes, self-adhesive patches, or tube-patching material, an adhesive, a piece of sandpaper or a metal grater (for roughing the tube surface to be patched), Special, thin wrenches are often required for maintaining various screw fastened parts, specifically, the frequently lubricated ball-bearing "cones".[57][58] and sometimes even a block of French chalk.), wrenches, hex keys, screwdrivers, and a chain tool. There are also cycling specific multi-tools that combine many of these implements into a single compact device. More specialized bicycle components may require more complex tools, including proprietary tools specific for a given manufacturer.
We've also released our first native 72V battery pack in a conventional downtube battery casing, assembled using the high power Samsung 27100 40T cells so that even with the small 8Ah capacity it is able to deliver 40-50A continuous currents. This is an ideal battery for fast and sporty offroad ebike builds, allowing powerful performance without the weight or complexity of most 72V setups (either two 36V packs in series or a large triangle frame battery).
Since fat tire electric bikes are suitable for a wider variety of situations than a standard cruiser or commuter e-bike, they have the potential to appeal to more people. For example, hunters and campers are ideal candidates for fat tire e-bikes, as they’ll benefit greatly from the heavy-duty tires and powerful motor when they’re navigating difficult wooded trails with lots of gear.
In the theoretical electric bike we considered up above, we had the dynamo/motor driving the back wheel directly, simply by pressing on the tire. Most electric bikes work a different way. They have compact electric motors built into the hub of the back or front wheel (or mounted in the center of the bike and connected to the pedal sprocket). Take a look at the hub of an electric bike and probably you'll see it's much fatter and bulkier than on a normal bike. You can read more about how these motors work in our main article about hub motors.

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.

DIY enthusiasts, with tens of thousands of converted bikes using throttle-only, 20+ mph kits, are now officially labeled Moped class. While these bikes handle and pedal-ride just as safely as the class 3 speed pedelecs in many cases, our DIY counterparts will be officially kicked out and left on their own for advocacy and legal acceptance in California. This is a big deal, without a class sticker, any DIY electric bike conversion kit is considered a Moped and not a bicycle.
Electric motorized bicycles can be power-on-demand, where the motor is activated by a handlebar mounted throttle, and/or a pedelec (from pedal electric), also known as electric assist, where the electric motor is regulated by pedaling. These have a sensor to detect the pedaling speed, the pedaling force, or both. An electronic controller provides assistance as a function of the sensor inputs, the vehicle speed and the required force. Most controllers also provide for manual adjustment.
There are no ADRs applicable to AA or AB category vehicles. There are ADRs for lighting, braking, noise, controls and dimensions for LA category vehicles, mostly referencing the equivalent UN ECE Regulations. An approval is required to supply to the market any road vehicle to which ADRs apply and an import approval is required to import any road vehicle into Australia.[5]
That aside, the Axis is a fantastic e-bike. At 'only' 16kg, it's almost lively by e-bike standards, but it also feels rock solid. It's geared too low in my opinion – I think it's fair to say I am not the target market – but in 8th, you can breeze on past the legally mandated, electrically-assisted 15.5mph. The hydraulic disk brakes will then bring you to a pleasingly rapid dead stop. The range and charging time are good, too. Cheap it is not, mind you.
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.
There's no question that electric bikes are far better for the environment than petrol-powered car engines. But that doesn't mean they're completely perfect. Making and disposing of batteries can be very polluting. Not only that, but an electric bicycle is still using energy that has to come from somewhere. You may think you're using clean green power, but the electricity you use for getting about might have come from a filthy old, coal-fired power plant or one driven by nuclear energy. (If you're lucky, of course, it might have come from solar panels or a wind turbine!) Electric bikes are nowhere near as environmentally friendly as ordinary push bikes, but nothing is ever perfect—and, as people often say, "the perfect is the enemy of the good." Electric bikes are certainly a step in the right direction. If everyone used them to get about instead of cars, global warming might be less of a problem, and the world would be a far cleaner and healthier place!
An electric bicycle is a bicycle with an electric motor used to power the vehicle, or to assist with pedaling. In many parts of the world, electric bicycles are classified as bicycles rather than motor vehicles, so they are not subject to the same laws as motor vehicles. Electric bicycles are one type of motorized bicycle. However, electric bicycles are defined separately and treated as a specific vehicle type in many areas of legal jurisdiction.
"Motor-driven cycle" means any vehicle equipped with two or three wheels, a power source providing up to a maximum of two brake horsepower and having a maximum piston or rotor displacement of 50 cubic centimeters if a combustion engine is used, which will propel the vehicle, unassisted, at a speed not to exceed 30 miles per hour on a level road surface, which does not require clutching or shifting by the operator.[138] The designation is a replacement for "scooter" and "moped;"[139] Vermont doesn't seem to have laws specifically for e-bikes.[140]

Class 1 makes great inroads to establish set boundaries for off road/natural surface trail access for eMountain bikes. There is fierce resistance from some mountain biking purists to allow ebikes on trails. BPSA and IMBA have done good work to justify the impact of class 1 ebikes on natural surface trails, and eliminate the wear-n-tear argument, though IMBA members are not 100% on board.
This dexterous electric dirt bike is recommended for anyone over the age of 14. It’s fitted with double suspension and big tyres to help you tackle tough terrain. You also get a good selection of gears, that gives you optimal control. The Razor can go as fast as 15 mph on average, and comes with an excellent braking system. The aesthetics are on point, and the racer look is sure to impress. Don’t forget your helmet!
"Bicycles" and "Electric Bicycles" are legally defined in the Texas Transportation Code Title 7, Chapter 551 entitled "Operation of Bicycles, Mopeds, and Play Vehicles" in Subchapter A, B, C, and D.[131] Under Chapter 541.201 (24), "Electric bicycle" means a bicycle that is (A) designed to be propelled by an electric motor, exclusively or in combination with the application of human power, (B) cannot attain a speed of more than 20 miles per hour without the application of human power, and (C) does not exceed a weight of 100 pounds. The department or a local authority may not prohibit the use of an electric bicycle on a highway[132] that is used primarily by motor vehicles. The department or a local authority may prohibit the use of an electric bicycle on a highway used primarily by pedestrians.

Since 2001, Canada's Motor Vehicle Safety Regulations (MVSR) have defined Power Assisted bicycles (PABs). They are currently defined as a two or three wheeled bicycle with an attached electric motor of 500W or less and which is capable of being propelled manually. Furthermore to meet the safety requirements set down by this legislation it must meet the following; when engaged by muscular power it must cease assistance when muscular power ceases or if powered by an accelerator controller cease power when braking and be incapable of providing assistance above 32 km/h and bear a label that is permanently affixed by the manufacturer and appears in a conspicuous location stating the vehicle is a power-assisted bicycle.[5][6]
Bicycle suspensions are used primarily on mountain bicycles, but are also common on hybrid bicycles, as they can help deal with problematic vibration from poor surfaces. Suspension is especially important on recumbent bicycles, since while an upright bicycle rider can stand on the pedals to achieve some of the benefits of suspension, a recumbent rider cannot.
In Quebec power-assisted bicycles are often classified similarly to standard pedal bicycles. They do not have to meet the conditions defined within the Canadian Motor Vehicle Safety Regulations (they are not classed as "motor vehicles"), but they do have to comply with federal regulations that define Power Assisted Bicycles. The Quebec Highway Safety Code defines a power-assisted bicycle as a bicycle(2 or 3 wheels that touch the ground) with an electric motor with a maximum power of 500W and a top speed of 32 km/h bearing a specific compliance label permanently attached by the manufacturer[30]. PABs are permitted on the road in the province of Quebec, but riders have to be 14 and over to ride the electric bicycle and if they're under the age of 18, must have a moped or scooter license.

"Electric power-assisted bicycle" means a vehicle that travels on not more than three wheels in contact with the ground and is equipped with (i) pedals that allow propulsion by human power and (ii) an electric motor with an input of no more than 1,000 watts that reduces the pedal effort required of the rider. For the purposes of Chapter 8 of this title, an electric power-assisted bicycle shall be a vehicle when operated on a highway.[65]


Hmm, I think it depends on the forest. My experience has been that if you have a Class 1 ebike and are riding respectfully, most places allow it. I have a sensitive knee and carry a doctor’s note citing disability laws in Colorado and have never been approached or asked by a ranger or fellow rider about the legality of my bike. That said, I have been using the really quiet and hidden Brose motor and I ride carefully and am friendly with everyone
Government regulation is written and administered with a broad, dull, painful axe. Regulations do not mix well with independent, maverick, DIY programs either. Vehicle regulations get started when there is either a visible tragedy, or a rising conflict with the status quo (like the SFO scooters program). The ebike community cannot afford a deadly accident especially if it involves others and the ebike or ebike rider are at fault. The Ebike community is up against a tough status quo that consists of pedestrians, motor vehicle traffic, the large well-funded and battle tested regular bicycle community, and the environment (especially for MTB riding and off-road use). 

Most of you are likely here for the electric bits, though. Those consist of a 500Wh user-swappable Bosch Powerpack battery and a 250W Bosch Active Line Plus motor that delivers 37lb-ft (50Nm) of torque and speeds of up to 20mph (32km/h). The battery takes up to 4.5 hours to reach a 100-percent charge and offers a range of up to 134 miles. With the battery and motor, it's markedly heavier than a comparable urban bike, weighing in at 46lb (20.8kg).

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.
Flyer Vollblut. A new rear motor bike from one of the most reliable E-bike makers. This model doesn't look as "heavy" as most other Flyer models. The Vollblut 500 has the 500W new Panasonic rear motor, front fork suspension, 28 inch wheels. It is in the same price range as the Stöckli and the Stromer. Flyer is known for top service and reliability, but it's a new model with a new motor ....
We spent 45 hours on research, videography, and editing, to review the top choices for this wiki. With rechargeable, battery-powered pedaling assistance, electric bicycles offer an increasingly viable alternative to fossil-fueled commuting, and e-bikes enable riders of various abilities to extend their cycling range. But the street legality of these hybrid machines remains a contentious issue, so be sure to check current state and local laws governing their operation before you hit the road. When users buy our independently chosen editorial picks, we may earn commissions to support our work. Skip to the best electric bike on Amazon.
The Domane+ e-road bike is the electric version of Trek’s popular Domane. It’s designed for riders who appreciate that bike’s reliable comfort and IsoSpeed technology but want the added fun and function of e-assist. It’s also the ideal companion for anyone coming back from injury, slower riders who want to mix it up with a speedy group, and couples with different fitness levels. A Bosch Performance Line Speed motor provides a very welcome 28 mph of pedal assist, and the 500Wh Powertube battery sleekly integrates into the down tube. Also integrated: front and rear lights, which are powered by the battery—no charging required.
To qualify as an electric-assisted bicycle under state law they need to have a seat and fully operable pedals for human propulsion, meet federal motor vehicle safety standards, an electric motor that has a power output of not more than 1,000 watts, maximum speed of not more than 20 mph (electric motor and human power combined), disengages or ceases to function when the vehicle’s brakes are applied, two or three wheels

I bought this bike from a dealer after extensive research on ebikes. The Elby is on par with European commuter ebikes at a better price point, you get a lot for your $ here. Elby is the complete package commuter: lights & a USB charger (for a phone or whatever) are integrated into the motor’s power supply and wired inside the frame. Rugged fenders have heavy-duty cross braces to attach baskets and whatnot. Thick Continental tires make for a comfy ride. The step-through frame is very convenient, built stout enough to carry me (200#) and two loaded baskets down hills and around curves with perfect stability. The motor on this bike is in the rear hub, and having it behind me makes it virtually soundless. The motor (BionX 500 watt) kicks in as soon as you start pedaling, but there is a
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.

Put the wheel with the electric hub on your bike and connect the brake components. Simply reverse the process you used to remove the wheel in order to reinstall it. Be sure to adjust the chain so it fits properly if you’re replacing the back wheel. If the bike has rim or cantilever brakes, simply close them over the new wheel using the lever. If the bike has disc brakes, put the pads back in place and secure them using the clips, springs, or cotter or retaining pin.[11]


In the early 1860s, Frenchmen Pierre Michaux and Pierre Lallement took bicycle design in a new direction by adding a mechanical crank drive with pedals on an enlarged front wheel (the velocipede). This was the first in mass production. Another French inventor named Douglas Grasso had a failed prototype of Pierre Lallement's bicycle several years earlier. Several inventions followed using rear-wheel drive, the best known being the rod-driven velocipede by Scotsman Thomas McCall in 1869. In that same year, bicycle wheels with wire spokes were patented by Eugène Meyer of Paris.[22] The French vélocipède, made of iron and wood, developed into the "penny-farthing" (historically known as an "ordinary bicycle", a retronym, since there was then no other kind).[23] It featured a tubular steel frame on which were mounted wire-spoked wheels with solid rubber tires. These bicycles were difficult to ride due to their high seat and poor weight distribution. In 1868 Rowley Turner, a sales agent of the Coventry Sewing Machine Company (which soon became the Coventry Machinists Company), brought a Michaux cycle to Coventry, England. His uncle, Josiah Turner, and business partner James Starley, used this as a basis for the 'Coventry Model' in what became Britain's first cycle factory.[24]
The handlebars connect to the stem that connects to the fork that connects to the front wheel, and the whole assembly connects to the bike and rotates about the steering axis via the headset bearings. Three styles of handlebar are common. Upright handlebars, the norm in Europe and elsewhere until the 1970s, curve gently back toward the rider, offering a natural grip and comfortable upright position. Drop handlebars "drop" as they curve forward and down, offering the cyclist best braking power from a more aerodynamic "crouched" position, as well as more upright positions in which the hands grip the brake lever mounts, the forward curves, or the upper flat sections for increasingly upright postures. Mountain bikes generally feature a 'straight handlebar' or 'riser bar' with varying degrees of sweep backwards and centimeters rise upwards, as well as wider widths which can provide better handling due to increased leverage against the wheel.
Cargo bikes and city bikes are common in the e-bike space, but until recently we haven’t seen that many performance road bikes. The Giant Road E+1 is a pedal-assist performance road bike that’s made for more than just commuting; the powerful motor can crank you up to 28 mph very quickly on the highest setting so you can rip the flats, join your local group ride, or blast through the mountains with far less effort than a traditional road bike. It won’t feel like a 16-pound race bike when you lean it into high-speed turns, but the endurance-oriented geometry allows for an aggressive position on the bike and keeps it nimble and agile at high speed.
E-bikes can boost bike usage, offer health benefits and use “an order of magnitude less carbon dioxide than a car traveling the same distance,” according to a 2016 research review published in the journal Transport Reviews.  In fact, access to an e-bike increased cycling trips and distances traveled – and nearly doubled the bike as a mode of transportation, observed one Norwegian study.
This article did a good job of trying to justify the assist speed limits but fell short of detailing how that can ever be effectively enforced. In reality the only enforcement that is going to work is applied speed limits to use of bikes and ebikes. For example, it makes sense that a bike lane on a street that the speed limit of vehicles is the speed limit of the bikes/ebikes. On sidewalks and shared pedestrian paths the speed limit probably does need to be in the 15-20mph range to match traditional bikes speeds on those paths.

I had gotten this to build an electric bike but I have never worked with wires before so I didn't realize that we needed to attach our own connectors to the wires. The person who I talked to at Joyisi was super nice and explained that to me and even offered to send me connectors for free. I had already ended up getting a different bike altogether though and so I just wanted to return the battery. But because I am returning it for my own reasons (as opposed to the battery being faulty), they would normally have me pay for return shipping and deduct the cost of shipping to me (which is a lot, because they are international) and the inspection fee from my refund, but they were super nice and offered to take on most of the costs and I would only have to pay for the return

Under the statute, mopeds must be registered. To be registered under Hawaii law a moped must bear a certification label from the manufacturer stating that it complies with federal motor vehicle safety standards (FMVSS). A moped must also possess the following equipment approved by the D.O.T. under Chapter 91: approved braking, fuel, and exhaust system components; approved steering system and handlebars; wheel rims; fenders; a guard or protective covering for drive belts, chains and rotating components; seat or saddle; lamps and reflectors; equipment controls; speedometer; retracting support stand; horn; and identification markings.
Experiments done in Uganda, Tanzania, and Sri Lanka on hundreds of households have shown that a bicycle can increase a poor family's income as much as 35%.[69][better source needed][70][71] Transport, if analyzed for the cost-benefit analysis for rural poverty alleviation, has given one of the best returns in this regard. For example, road investments in India were a staggering 3–10 times more effective than almost all other investments and subsidies in rural economy in the decade of the 1990s. What a road does at a macro level to increase transport, the bicycle supports at the micro level. The bicycle, in that sense, can be an important poverty-eradication tool in poor nations.

After you decide which style of e-bike you want, consider the class. In the U.S., there are three classes defined by the type of assist and how fast the motor will propel you. Most electric bikes sold are class 1 or 3. Class 1 bikes have a motor (max 750w) that assists while you’re pedaling, up to 20 mph. Class 3, also known as “speed pedelec,” can also have up to a 750w motor, but it can assist you up to 28 mph. Both are allowed in most states and cities without requiring a license. Class 2 models have throttles that don’t require the rider to pedal in order to get a boost. They’re allowed on most streets, bike lanes, and paths, but are less popular than the other classes and not covered much here (because not only do we still love to pedal, we also prefer the greater distances that pedal-assist bikes can cover).
Not all electric bicycles take the form of conventional push-bikes with an incorporated motor. Some are designed to take the appearance of low capacity motorcycles, but smaller in size and comprising of an electric motor rather than a petrol engine. Bicycles of note include the Sakura electric bicycle, which incorporates a 200W motor found on standard e-bikes, but also includes plastic cladding, front and rear lights, and a speedometer. It is styled as a modern moped, and is often mistaken for one based on its similarity in appearance.
The federal Consumer Product Safety Act defines a "low speed electric bicycle" as a two or three wheeled vehicle with fully operable pedals, a top speed when powered solely by the motor under 20 mph (32 km/h) and an electric motor that produces less than 750 W (1.01 hp). The Act authorizes the Consumer Product Safety Commission to protect people who ride low-speed electric vehicles by issuing necessary safety regulations.[63] The rules for e-bikes on public roads, sidewalks, and pathways are under state jurisdiction, and vary.
Vehicles with an electric power and power of less than 300W are classified as "not a motor vehicle". Such electric bicycles must comply with the same rules as bicycles. You must wear a helmet even on a scooter or bike under 300W. If the power is over 300W or a combustion engine is used it is a "low powered vehicle" and the moped rules apply. Specifically, a drivers license and registration are required.

The handlebars connect to the stem that connects to the fork that connects to the front wheel, and the whole assembly connects to the bike and rotates about the steering axis via the headset bearings. Three styles of handlebar are common. Upright handlebars, the norm in Europe and elsewhere until the 1970s, curve gently back toward the rider, offering a natural grip and comfortable upright position. Drop handlebars "drop" as they curve forward and down, offering the cyclist best braking power from a more aerodynamic "crouched" position, as well as more upright positions in which the hands grip the brake lever mounts, the forward curves, or the upper flat sections for increasingly upright postures. Mountain bikes generally feature a 'straight handlebar' or 'riser bar' with varying degrees of sweep backwards and centimeters rise upwards, as well as wider widths which can provide better handling due to increased leverage against the wheel.


It should be noted that the definition as written does not define the power of the motor in Watts as is conventionally done for electric bicycles but rather in brake horsepower. Thus for an electric bicycle, motor kit, or electric bicycle motor that is not rated by the manufacture in brake horsepower but rather in Watts a conversion must be made in the units a conversion which is not given in the code of the law and thus the court will have to consider a factor of conversion that is not directly encoded in the law. Industry standard conversion for Watts to horsepower for electric motors is 1 horsepower = 746 watts.[105] Acceptance of that conversion factor from industry, however, as interpretation of the law is subject to the process of the courts since it is not defined specifically in the law.
In some countries mixed systems, i.e. pedaling and/or using a throttle is legal. In EU countries and Switzerland this is not the case. I.e. you can buy an electric scooter, but this is not considered to be an e-bike in the moped / light scooter category. That kind of hack is probably more difficult, unless the original design has been modified to fit with (s)Pedelec specs. E.g. The Ezee models are of that kind and modifications to revert to the original does not seem to be too difficult...
The Surly Big Easy is the Cadillac of the bike lane. The company’s new longtail e-cargo bike exudes a “they don’t make ’em like this anymore” stature, thanks to a beefed-up chromoly steel frame rolling on tough 26x2.5-inch tires. And because it’s a class 1 e-bike, you can actually ride it in the bike lane, too. The 7-foot-long, 67-pound bike won’t play well with your third-floor walk-up, so it’s best to think of it as a car supplement or replacement—that’s what Surly intended, anyway, as evidenced by the $5,000 price tag. However, if you’re ready to commit to the cargo bike life, you’ll struggle to find a stronger platform for achieving bike commuter nirvana.
At first glance, Wing’s e-bikes share some design features with Dutch e-bike company VanMoof’s flagship bikes, most noticeably the elongated top tube (23.3 inches) with embedded front and rear lights. There are differences — VanMoof’s battery is embedded in the frame, while Wing’s is external — but to look at them side-by-side, one could easily conclude that Wing is just a less-expensive version of the VanMoof.
Bicycles featuring pedal power were developed during the subsequent decades of the 19th century, with the most emblematic example being the bicycle we know today as the Penny-Farthing. The bike was named based on the substantial difference in its wheel size resembling the larger and smaller Penny and Farthing coins, respectively. These bicycles were wildly popular among the well heeled upper classes of Europe and America despite their penchant for launching riders head first over the large wheel, not to mention their relative difficulty to mount and dismount.
In Opinion No. 2007-00602 of the Attorney General, Jim Hood clarified that a "bicycle with a motor attached" does not satisfy the definition of "motor vehicle" under Section 63-3-103. He stated that it is up to the authority creating the bike lane to determine if a bicycle with a motor attached can be ridden in bike lanes. No specifications about the motor were made.
The Freedom’s motor is more powerful than the VanMoof Electrified S — 350w vs 250w — but the VanMoof is technologically superior, with touch-sensitive display, enhanced security system, and an “invisible” lock built right into the rear hub. The Dutch-made bikes are also more expensive: VanMoof’s Electrified X2 and S2 list for a discounted $2,598, while Wing’s e-bikes are available now for an “early bird” price of $1,295; if you order later, it’ll cost $1,695 — which is still almost $900 less than the VanMoof.
Biking is awesome, but biking uphill is not. Commuting by bike is environmentally friendly, fun and good for your health, but presenting your sweaty self to your office coworkers in not fun at all. Fortunately, there is a solution! Electric bicycles offer the same great benefits as traditional bicycles including cost savings, health improving, plus some additional advantages like efficiency in climbing hills, less stress on knees and joints, which is convenient for people of all ages and health.
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