The hydroformed aluminum frameset features sleek lines, and SRAM XO and Force components comprise the drivetrain. A carbon crank from FSA ensures efficient power transfer and keeps the weight down. The wheels feature straight-pull spokes and deep-dish rims for aerodynamics. Tern uses a simple three-step folding process, and the bike can roll when folded for easy transport. Price: $3000.
The 20-inch Schwinn Loop, Amazon’s best-selling folding bike at around $200 currently, isn’t really designed for commuting (despite the Amazon verbiage). It has a bulky step-through frame, and in our tests it offered a heavy, sluggish ride—Citi Bikes (those blue three-speed bike-share behemoths) often passed me on the bridge, and I had no hope of fitting it through the subway turnstiles. If you plan to use your folding bike regularly, do yourself a favor and spend more.
For what it’s worth, the Dahon Mariner D7 received many accolades within the world of folding-bike websites. (The D8 hasn’t been out long enough for there to be any reviews.) Folding Bike Guru found few flaws, giving it an “excellent” rating of nine (out of 10) and calling it “[a] very solid and outstandingly-performed folding bike.” Folding Bike 365 also gave the Mariner D7 high marks, especially for value: “A fantastic, no-frills, well built commuter bike which delivers as promised. Highly recommended.” Ricky Do of BikeFolded acknowledges the Mariner D7’s best-seller status, writing, “Once I tested the bike, I was not surprised with the success at all.” Although none of these reviewers are transparent about their possible relationships with bike manufacturers, I felt they were reasonably legit—the reviews being the product of enthusiasts indulging their obsession—and the best of what’s out there. As for mass-media outlets, not many seem to be looking at the folding-bike category as a whole, though Popular Mechanics did choose the Mariner D7 as its mobility pick in its recent best commuter bike recommendations. Amazon shoppers also agree at this writing, giving the Mariner a 4.3-star rating (out of five) across more than 100 reviews.
Let's start with the obvious; you prefer a folding bike because you don't have space. Maybe you lack a lot of space at work, or you live in a tiny apartment. In fact, if you live in a tiny apartment that is located in a walk-up, then you probably know just how insane it is to lug a bike up and down several flights of stairs. If any of these conditions apply, you should probably own a folding bike.
Strida - what is with these Brits? They certainly are a creative bunch when it comes to folding bikes. The British Strida truly reinvents the concept of the bicycle. Its triangle frame is like nothing you have ever seen and its greaseless Kevlar belt drive (rated to last 100,000 miles) will never smudge your clothes. It folds in seven seconds (the shortest folding time of any model featured here) into a rolling, 22 pound walking stick with the dimensions of 44" X 20" X 20". This one is sure to turn heads. The Strida ranges in price from $430 to $680, depending on how many of the many nice accessories you get. T.A. members get free shipping just for mentioning T.A. in their phone or internet order. www.strida.com.
Controllers for brushless motors: E-bikes require high initial torque and therefore models that use brushless motors typically have Hall sensor commutation for speed and angle measurement. An electronic controller provides assistance as a function of the sensor inputs, the vehicle speed and the required force. The controllers generally allow input by means of potentiometer or Hall Effect twist grip (or thumb-operated lever throttle), closed-loop speed control for precise speed regulation, protection logic for over-voltage, over-current and thermal protection. Bikes with a pedal assist function typically have a disc on the crank shaft featuring a ring of magnets coupled with a Hall sensor giving rise to a series of pulses, the frequency of which is proportional to pedaling speed. The controller uses pulse width modulation to regulate the power to the motor. Sometimes support is provided for regenerative braking but infrequent braking and the low mass of bicycles limits recovered energy. An implementation is described in an application note for a 200 W, 24 V Brushless DC (BLDC) motor.
Lightweight folding bikes: Of course, if you intend to be hoisting the bike on and off trains, then it’s understandable that you want it to be light. This can be achieved though using a lighter frame material. Brompton have recently introduced titanium to their range and there are brands making carbon folders. Higher quality components will also reduce the weight, as will opting for fewer gears – such as a singlespeed version – but this will only really suit someone who doesn’t intend to come across many hills in their use of the bike.
Back into the ‘fully folding world’, we’ve got the Coyote Connect. This 20″ bike comes with a 24V battery, has a max speed of 15 mph and will go for around 20 miles. It’s got a Shimano Tourney 6-speed gear system, Tektro V-brakes with Kenda tyres. The frame is alloy, but the forks are steel – which will add to comfort bit will be a tad heavier than most.
An electric bicycle, also known as an e-bike, powerbike or booster bike, is a bicycle with an integrated electric motor which can be used for propulsion. Many kinds of e-bikes are available worldwide, from e-bikes that only have a small motor to assist the rider's pedal-power (i.e., pedelecs) to somewhat more powerful e-bikes which tend closer to moped-style functionality: all, however, retain the ability to be pedalled by the rider and are therefore not electric motorcycles.