Suzuki's Variable-Miller-Cycle Non-Throttle-Valve

Discussion in 'Technical' started by KZ, Apr 15, 2009.

  1. KZ

    KZ Ol'Timer

    I came across this article on Suzuki Motor's website, souds interesting but I'm not sure if it's really as innovative as Suzuki claims or if it's just a way to generate some buzz. Read the second last sentence.

    New-generation motorcycle engine With huge potential With huge potential

    Suzuki Innovations Produce Environment-Friendly Variable-Miller-Cycle Non-Throttle-Valve Engine

    As market demand for environment-friendly performance intensifies, automakers are accelerating development of hybrid engines, fuel cells and other power source replacements for petrol engines. Designing such alternative power sources to meet high-performance motorcycle standards is a huge challenge. Nevertheless, Suzuki is deep into development of a continuously variable Miller-cycle non-throttle valve engine, an innovative power source that offers hugely improved fuel efficiency and output characteristics in a form that still delivers the merits of two-wheeled vehicle performance.

    The significant difference between this next-generation engine and a conventional one is the control system. Conventional Otto-cycle engines are designed to optimize the cam profile when the throttle valve is fully open and control the output power by closing the butterfly-shaped throttle valve. Inevitably, this system caused large pumping losses that result in mediocre fuel economy and output.

    Suzuki’s Variable-Miller-Cycle Non-Throttle-Valve engine, in contrast, innovatively controls the output power through variation of valve lift volume. The engine uses Suzuki’s original three-dimensionally-mapped cams. This novel cam is shaped to create a three-dimensionally-mapped curve line according to the variation of three elements of valve lift characteristics valve lift amount, valve lift event and valve timing. The cam’s complex contact phase, operated by a drive-by wire controlled motor, slides along the accelerating shaft. The valve lift range is continuously varied by electronic control, enabling complete control of the valve lift characteristics and great reduction of pumping losses, a major drawback of throttle valve operation in conventional petrol engines.

    Intake cam lift characteristics were also altered to Miller-cycle-that is, to expedite the closing timing to raise expansion rate-so that combustion energy can be converted efficiently to revolving torque. Though the Miller-cycle engine does lessen engine braking torque, Suzuki has compensated with an original engine brake control technique that maintains braking torque equivalent to, or greater than, conventional engines.

    With these innovative technologies, the novel engine achieves fuel economy about 40% higher than that of an identically sized conventional engine, a significant improvement in environmental friendliness. The new engine also optimizes acceleration performance according to road conditions, and offers the rider several modes of accelerator response characteristics such as “sporty” and “ecological.” The simple compact structure and excellent performance at high engine-speed range make this engine ideal for a two-wheeled vehicle. This is truly the advent of a next-generation engine with huge potential.
  2. KZ

    KZ Ol'Timer

    Whoa, something must have tripped up the software - over 4000 views in less than one day?!
  3. DavidFL

    DavidFL Administrator Staff Member

    Yeah you copied & pasted in (from ___ ), importing some weird characters that sent it all ballistic. I think it's fixed now.

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