I bought the 52v 13ah for my 1000w BBSHD build and it is working great. My bike tears it up pretty good with this battery pack. Hopefully I don't run into any problems but so far so good. One thing I learned the hard way - if you use a 52v pack with the 1000w bbshd your battery meter will no longer be accurate. That was one tough ride home with my heavy fat bike!
However, Emu sells a little foldable number if that's your bag. The Emu Crossbar is for  town commuters that require a sweet ride that's backed up by solid Shimano Nexus hub gears and Tektro brakes, which are adequate if not the best on the market. Riding is smooth and easy, with the crank moving sensor doing its best to iron out any gaps in power delivery.
Another style is the recumbent bicycle. These are inherently more aerodynamic than upright versions, as the rider may lean back onto a support and operate pedals that are on about the same level as the seat. The world's fastest bicycle is a recumbent bicycle but this type was banned from competition in 1934 by the Union Cycliste Internationale.[43]

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'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!
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).
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]
If you want an e-bike that positively sprays tech out you, try the Volt Axis on for size. It takes the GoCycle GS's combo of folding, lightweight frame and disk brakes and adds automatic gears, if you please. These react to your speed and pedalling effort. So you automatically gear down when you stop at traffic lights – although what self-respecting cyclist does that? – and then back up as you accelerate.

Electric-assisted bicycle operators must follow the same traffic laws as operators of motor vehicles (except those that by their nature would not be relevant). The bicycles may be operated two abreast. Operators must generally ride as close as is practical to the right-hand side of the road (exceptions include when overtaking another vehicle, preparing for a left turn, and to avoid unsafe conditions). The bicycle must be ridden within a single lane. Travel on the shoulder of a road must be in the same direction as the direction of adjacent traffic.

The Bosch Performance CX is still one of the most popular motors on the market. It’s synonymous with reliability, but it’s getting on in years. The newly presented Active Line looks like a glimpse into Bosch’s future: it is more compact, lighter, has less internal resistance, and uses a large chainring. It can only be a matter of time before Bosch releases a new performance motor.
A 2008 market survey showed that the average distance traveled in the Netherlands by commuters on a standard bicycle is 6.3 kilometres (3.9 mi) while with an e-bike this distance increases to 9.8 kilometres (6.1 mi).[79] This survey also showed that e-bike ownership is particularly popular among people aged 65 and over, but limited among commuters. The e-bike is used in particular for recreational bicycle trips, shopping and errands.[79]

And let’s not forget the economic advantages of owning an e-bike. The annual cost of running a new family car is, on average, about $9,000 per year. Running an electric bike costs around $400 per year. And while filling a gas tank costs around $30, recharging an electric bike battery costs only about 50 cents. A tank of gas may get you further, but not 60 times further!

It's a solid e-bike, but it's also very heavy one for a folding bike. I found it difficult carry when the bike is folded as the carrying handle is useless, and the center of gravity is towards to the rear wheel so one has to find a place in the rear of the bike to pick it up. Even when the bike is folded, it's bulky and heavy, It's difficult to walk with it while carrying it. It's easy to hurt one's back if he or she is not careful. I would not recommend carrying this bike up or down stairways.
In cities where bicycles are not integrated into the public transportation system, commuters often use bicycles as elements of a mixed-mode commute, where the bike is used to travel to and from train stations or other forms of rapid transit. Some students who commute several miles drive a car from home to a campus parking lot, then ride a bicycle to class. Folding bicycles are useful in these scenarios, as they are less cumbersome when carried aboard. Los Angeles removed a small amount of seating on some trains to make more room for bicycles and wheel chairs.[65]
But the whole is also influenced by the sensory systems which are very different from model to model. E.g. A typical 2013 Panasonic system requires pedalling for optimal support (55/minute?) and has both a pedalling frequency and a speed sensor. You don't get much assistance if you pedal very slowly or very fast. Typically, a rear motor has a force sensor, i.e. you get lots of support fast when you start pedalling in a low gear, i.e. it will "feel" your need for assistance.
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 with an electric motor. PABs are permitted on the road in the province of Quebec.
Included in this shipment are the much awaited 3540 motors with their slick "UFO" design. These are the replacements for the older square style "H" motors, you may have noticed that this change was implemented last year with the 3525 front and rear motors. As always, we have the motors customized with a 10K NTC thermistor for thermal rollback using the CA3.
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!
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.
Photo: Left: The hub motor of an electric bike. Right: If you took off the casing, this is the kind of thing you'd see. It's a simple brushless motor from a PC cooling fan, but it works in broadly the same way as a bike's hub motor. There's a static part made up of four electromagnet coils (left) and a rotating part (right) made from a permanent magnet (the gray ring) that clips onto it. When the coils are energized in sequence, they generate a magnetic field that makes the permanent magnet and fan spin around. At a glance, a hub motor looks much like an ordinary bicycle hub, but look closer and you'll find it's a lot more bulky.
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.