Thinking About Kawasaki’s New Electrics

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Kevin Cameron has been writing about motorcycles for nearly 50 years, first for <em>Cycle magazine</em> and, since 1992, for <em>Cycle World</em>. (Robert Martin/)

Kawasaki has released a pair of 400-sized commuter bikes that look like motorcycles. They have full-sized 17-inch wheels, are close to 300 pounds in weight, and have normal bike geometry: 53.9-inch wheelbase with conventional sportbike 24.4-degree steering rake and 3.7-inch trail, giving familiar quick, direct steering. Suspension is also motorcycle-standard; the 41mm front fork gives 4.7 inches of travel and the rear 5.2 inches, with a four-position rear preload adjustment to ease carrying a passenger. ABS brakes are a single 290mm (11.4-inch) front disc and the usual smaller single disc at the rear.

Related: Kawasaki Ninja e-1 and Z e-1 Details Emerge

Underneath the bodywork of the Kawasaki Ninja e-1 and Z e-1 there is much that looks like a conventional sportbike: trellis frame, 53.9-inch wheelbase, 24.4-degree rake, and 3.7-inch trail. (Kawasaki/)

Back when electric bikes were first emerging, a primary strategy was to look for areas of performance in which the electric could equal or exceed internal combustion engine (ICE) performance. Batteries—then and now—are heavy for the amount of energy they store, but can deliver tremendous power for short periods of time. The usual result of designing in this way was a bike with fabulous acceleration, impressive top speed, but with short range and excessive weight close to 600 pounds.

Always distinguish in your mind between power and energy. Power is the rate of doing work, so 1 hp is the ability to lift 550 pounds at a rate of one foot every second. Energy tells us how long that power can be delivered. Batteries are great at delivering power, but remain limited in the energy they can store.

Electric drive can be wonderful—smooth and easily controllable. It is what much of the electronics on ICE-powered motorcycles attempts to do: To give smoothly controllable power.

Another early direction of design was based on making a commuter vehicle needing much less battery weight. Many cute designs were produced, based on the idea of a few miles of commuting, with recharging occurring in the hours of darkness. That was a workable concept but the design was usually aimed at buyers who were most comfortable with a non-motorcycle look—call them the New Riders. They recall to my mind the numbers of US college students of the late 1950s/early ‘60s who bought Italian Vespa and Lambretta scooters, rode them until they graduated, and then sold them on. Riding a scooter did not mark you as a “Rebel Without a Car.” Scooters were stylish and well accepted, but were best adapted to urban use with their small wheels and modest power.

Two removable batteries will be charged overnight by most users in between commuting. (Kawasaki/)

At present, a lot of planners have understood that riders are not going to just cross off where it said “internal combustion engine” and substitute “electric” and then ride off into the sunset. Big powerful electrics have not taken the world by storm, being heavy, expensive, and limited either in range or in convenience in finding charging points when needed. If you want to make an electric motorcycle take the place of your previous ICE-powered bikes, be prepared to put in some planning effort.

So here is a new take on the commuter electric: an electric that looks like a motorcycle and handles like one. These bikes are light because they aren’t carrying enough battery to go far at other than city-suitable speeds. The claimed range of about 40 miles is commuter-OK, as is the overnight 7.5-hour recharge (the two batteries are removable for remote charging).

In normal operation motor power is limited to 6.7 hp which is unimpressive compared with the more than seven times greater power of an ICE-powered Kawasaki 400. But what electrics do best is accelerate. There is also an e-Boost feature, allowing use of 12 hp for 15 seconds. These bikes will not be left behind by urban traffic and they are not going to embarrass you by looking like a science fair project. These bikes look like proper motorcycles.

Related: 2024 Kawasaki Ninja E-1 and Z e-1 Electric Motorcycles Announced

Kawasaki’s Ninja e-1 and Z e-1 look like proper motorcycles. (Kawasaki/)

Because useful information about the state of battery charge is on the thin-film dash display, it and the vehicle’s lights are powered by a separate 12V battery.

When you read the specs you find that the motor is “synchronous.” What that means is that it is driven by alternating current from the bike’s power supply, and that the motor’s rotor spins in step with the AC frequency being generated in the power supply. AC synchronous drive is highly efficient and because the motor is brushless, there is nothing to wear out. This is the type of drive used in premium electric vehicles. The power supply converts the 50.4 volts of direct current (DC) from the Li-ion battery into the AC variable-frequency power required to drive the motor across its wide rpm range.

Kawasaki’s e-Boost feature allows the Ninja e-1 and Z e-1 to stay ahead of the masses at stoplights during the morning commute. (Kawasaki/)

The motor drives through a primary gear reduction, and by chain from the reduction shaft to the rear wheel. There is no clutch so first-timers do not have to master clutch-throttle sync to accelerate from rest. With the key on, turn the throttle and go.

To help first-timers handle the weight during parking or positioning, a Walk mode is provided, giving 3 mph forward and 1.8 mph reverse. You’ll soon get the hang of it.

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