The pedals on a motorised bicycle must be the primary source of power for the vehicle. If the motor is the primary source of power then the device cannot be classed as a motorised bicycle. For example, a device where the rider can twist a throttle and complete a journey using motor power only without using the pedals, would not be classed as a motorised bicycle.
The word bicycle first appeared in English print in The Daily News in 1868, to describe "Bysicles and trysicles" on the "Champs Elysées and Bois de Boulogne". The word was first used in 1847 in a French publication to describe an unidentified two-wheeled vehicle, possibly a carriage. The design of the bicycle was an advance on the velocipede, although the words were used with some degree of overlap for a time.
To help the rider find the perfect fit, the stem is adjustable. The bike also boasts dynamo powered lights alongside hydraulic disc brakes. The bike will suit riders from 4 ft 10 to 6 ft 5, and also integrates with a child seat. The total weight is 22.5kg, making it admittedly a fairly hefty folder – but that’s fairly uniform across electric versions.
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.
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.
Haibike ships the HardNine with 29-inch tires, 180-millimeter hydraulic disc brakes, a 100-millimeter front suspension fork, and a nine-speed Shimano shifting system. The bike’s LCD readout is affixed to the handlebars and displays the current speed, level of charge, remaining range, and current pedal assist mode. The company says the battery can be completely recharged in just four hours, minimizing downtime between rides.