Hybrid Diesel Electric Motorcycle

eCycle plans to introduce the hybrid motorcycle to beta testers in 2002.

The Principles of Operation

Vehicles for personal transportation generally spend more time cruising than they do accelerating. The enabling benefit of a parallel hybrid powertrain, such as that used by eCycle, is the separation of the vehicle requirements for acceleration and for constant speed, steady-state travel ("cruising"), and the subsequent separation of the energy storage requirements for acceleration vs. cruising.

Since electric motors can deliver maximum torque at zero rpm they are ideally suited to accelerating a vehicle. However, the range of a fully electric vehicle is controlled by the need for practical, economical electricity storage. Internal combustion engines that are sized for both acceleration and average power loads (as are the engines in conventional motorcycles and automobiles) are too large and inefficient when providing just the average power required for steady-state cruising. They consume more fuel and create more pollution than an engine sized only for the average load. These vehicles benefit from a large range of travel that is only limited by the amount of fuel that can be carried.

Either type of power source (a motor or an engine) when used alone has inherent limitations and problems to overcome, but when combined into a single system the two technologies are complementary and these limitations and problems are eliminated. The eCycle powertrain provides maximum efficiency while supplying power for the average load. Acceleration of the motorcycle is handled by the electric motor. The resulting hybrid powertrain creates a low-polluting, high efficiency vehicle with performance, handling and range of travel that are superior to conventional vehicles.

Designed along these principles, the eCycle hybrid motorcycle functions in the following manner:

1. To accelerate from a standstill, the control system senses the throttle input and then delivers torque to the electric motor. This causes the vehicle to begin moving forward and also causes the engine to begin spinning. At low speeds, no fuel is delivered to the engine, so the engine does not yet provide any power.
2. At approximately 12mph, or an equivalent engine speed of 1500rpm, the vehicle control system directs the fuel injection to begin spraying fuel into the engine. The motorcycle then receives torque input from both the diesel engine and the electric motor.
3. Once up to cruising speed, the electric motor no longer provides torque to the vehicle. Instead, since it is spinning in conjunction with the engine, the electric motor is used to very efficiently generate electricity to recharge the battery pack.
4. While cruising at a steady speed, if the control system senses more throttle input (for further acceleration to a higher speed), the electronics will re-engage power delivery to the electric motor. The torque added by the electric motor accelerates the vehicle. Once the desired speed is achieved, the electronics re-adjust and re-commence charging the battery.

The fully electronic power management of the eCycle allows the engine and electric motor to integrate seamlessly with each other. Only the sound of the engine starting and stopping (above/below 12mph) gives the rider an obvious indication of the complex process that is taking place.

Chassis

Front Suspension: 1.75" (44mm) Inverted Fork
7.5" (190mm) Travel
Rear Suspension: Penske Racing Coil-Over Mono-Shock,
Ride-Height Adjuster 5" (127mm) Travel
Front Brake: Grimeca Single Four-Piston Caliper
12.6" (320 mm) Disc
Rear Brake: Single One-Piston Floating Wave Rotor
8.5" (215.9mm) Disc
Front Wheel: Grimeca 17 x 2.75" Aluminum
Rear Wheel: Grimeca 17 x 2.75" Aluminum
Front Tire: Pirelli MT75, 110/70-17
Rear Tire: Pirelli MT75, 130/70-17
Rake/Trail: 24.0 Deg./3.9" (98.3mm)
Wheelbase: 52.0" (1321mm)
Seat Height: 28.0" (711mm)
Weight: 230lbs. (105kg)

The eCycle chassis is specifically suited to a hybrid propulsion system. It is made of steel and aluminum to minimize weight and to provide heat sinking for the battery pack and electronic components. The small engine fits easily within the confines of the frame. The battery pack is located low in the chassis to provide exceptional handling. The electric motor and driveline are engineered along the lines of a modern racing car - carrying loads and integrating as many functions as possible into the fewest number of components.

The tube frame used to carry the front fork and the battery pack is made of steel and joined by brazing and welding. The frame design was refined using FEA (finite element analysis). Zinc treated for corrosion resistance and powder-coated for durability, the frame is light, strong and tough.

The tube frame integrates with an aluminum box-section sub-frame that carries the rear suspension and driveline. The two main load-bearing members of the sub-frame assembly also perform other functions vital to the motorcycle - one side doubles as the main heat sink while the other side houses the transmission and picks up the rear suspension.

Suspension

The front suspension is an inverted fork made by FAR. The rear suspension is a single sided swing arm with a built-in caliper and a coil-over Penske mono-shock. eCycle is proud to be the 1st OEM customer of Penske Racing Shocks.

Styling

The bodywork is a combination of parts specially designed and/or modified to suit the eCycle. The side panels are made of color impregnated, thermoformed ABS plastic.

The lamps employed for the tail/brake light and turn signals are high flux density type LEDs (light emitting diodes), similar to what you see in the spoiler of a sports car. LEDs illuminate quicker, last much longer then a conventional light bulb (over 100,000 hours) and draw about 1/5 the average current of an incandescent bulb. It is attention to details such as this that make the eCycle a most efficient motorcycle.

Powertrain - Engine

While our 125cc rocker crank engine remains in development, we are utilizing an existing power plant in modified form to our advantage. The Yanmar 219cc, single cylinder, direct- injected, 4-stroke diesel engine provides high torque and efficiency. It exceeds our initial expected performance requirements. It is very well made, durable and serviceable.

Transmission

The eCycle transmission is a 2-speed, constant mesh, 3-shaft design utilizing ball and needle bearing construction with custom rolled gears. Low gear features an over-running clutch for smooth shifting and safety. The transmission drives the rear wheel via a Gates Polychain II belt.

Battery Pack

The hybrid battery pack utilizes ten 12V 5.0Ah sealed lead acid batteries. They are series connected to yield 120VDC nominal voltage. The total weight of the battery pack is only 44lbs.

Motor

The eCycle hybrid motorcycle uses the eCycle model MG24 motor with a special housing in its drivetrain. This is a 3-phase, permanent magnet, brushless motor rated at 5kw continuous and 15kw peak power. In the hybrid motorcycle, the motor sees up to 120VDC with a peak current of 70 Amps.

Though initially designed for our motorcycle, eCycle has developed a full range of motors that are ideally suited to numerous applications in industry and in other small vehicles.

Vehicle Electronics

At the heart of the eCycle is our programmable controller. The controller serves as the comprehensive management system for all of the vehicle subsystems. Among the functions controlled are: throttle input from the rider; power electronics, which is delivery of electricity to the motor for power and from the motor (generator) for regeneration; regulation of the compression release mechanism and control of the electronic dashboard display.

Target Performance Specifications
Fuel Consumption: 180mpg
Est. top speed: 80mph
0-60mph: 6.0sec
Weight: 230lb.

The Original Story from: ecycle.com