Electric motorcycles and scooters are swiftly and silently emerging in our midst. Sales are set to reach 60m units by 2024, creating a world market worth $55bn, according to research-based consultancy Global Market Insights.
The market growth is supported by a fast-growing array of bikes on offer from specialist and mainstream manufacturers, ranging from the world’s fastest production bike, California-based Lightning Motorcycle’s 350km/h LS-218, to German bike-maker BMW’s C Evolution scooter.
Whether sports bikes or urban-mobility scooters, electric motorcycles’ performance and versatility have improved dramatically in recent years.
“This industry is relatively new, but the pace of development has been so fast it’s only matched by the IT sector,” says Brian Wismann, vice-president of product development at California-based Zero Motorcycles, which started out by adding electric engines to beefed-up mountain bikes just over a decade ago.
Since then, the company has evolved into a manufacturer of full-size motorbikes, such as its Zero SR, which does 0 to 96km/h in 3.3 seconds, delivers a top speed of 164km/h, and has an extended range of 317km if an optional “power tank” is included – an extra battery that fits in a luggage compartment.
“The torque these electric motors provide is quite astonishing, and their range has increased significantly too,” says Wismann. He attributes the improvements to the combination of increasingly sophisticated electric powertrains with electronic systems that manage the batteries’ charge and thermal performance.
Ridin' through this world... BMW's electric C Evolution Scooter (Credit: BMWBlog)
Designing safe battery cases that release heat from the batteries is also vital, says Florian Kirmayer, project leader for BMW’s C Evolution scooter.
“As the housing of the traction battery has to be massive for crash issues and waterproofing, it was decided to make it part of the chassis,” he says.
Indeed, although BMW initially planned to merely fit an electric powertrain and integrate the company’s i3 cell modules in a conventional motorbike, “in the end we developed a completely new vehicle,” says Kirmayer.
“The package of electrical components was completely different to the ones in a classical vehicle,” he says, and integrating “the cell modules in two layers, combined with cooling and the control electronics, was very demanding”.
Beyond the electric and electronic systems, pioneering engineers are also coming up with motorcycles that are safer and easier to use than conventional two-wheelers.
Spain’s VMS Automotive, for instance, has developed a three-wheeler concept with two electric motors that power one rear wheel each.
Harley-Davidson has been developing an electric motor for years (Credit: iStock)
The design is practical, as “when splitting the rear drivetrain we created a 92-litre luggage space between the wheels – enough for a suitcase,” says technical director Florentino Miguez.
The two separate engines also enabled VMS to add a torque vectoring system, which varies the amount of torque to each wheel, improving road grip and handling. This is coupled with a mechanical tilting system, made up of levers and pull- and push-rods, which improves the bike’s dynamic performance.
“It is both safe and fun,” says VMS’s managing director Pablo Campos. “You really feel as if you’re never going to fall.”
Manufacturers are also improving the connectivity of bikes, with ever more user-friendly solutions such as improved screens and in-helmet electronics that aid communication and navigation.
Even fully autonomous electric bikes are on the cards. VMS is working on a stability system based on Segway principles such as using tilt sensors and gyroscopic sensors.
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