Browse Publications Technical Papers 2004-01-0989
2004-03-08

Paradoxical Approach to Improve Fuel Economy for Small Practical Motorcycles 2004-01-0989

Motorcycles have been classified by engine displacement from commercial and legal demands. If this restriction on displacement were removed, what could be done to improve fuel economy? “Down sizing” would be an obvious idea. However this paper proposes a quite inverse concept, i.e. a large displacement lower speed engine. Mechanical friction in four-stroke engines generally decreases in proportion to the square of engine speed. Thus mechanical efficiency should be better at lower operation speeds. According to this concept, developing a 200cm3 experimental engine was successful in improving fuel economy by 79% in the ECE40 mode and by 97% at 60km/h cruise condition, compared to the 100cm3 original engine.

SAE MOBILUS

Subscribers can view annotate, and download all of SAE's content. Learn More »

Access SAE MOBILUS »

Preview Document Add to Cart
Members save up to 16% off list price.
Login to see discount.
Special Offer: Download multiple Technical Papers each year? TechSelect is a cost-effective subscription option to select and download 12-100 full-text Technical Papers per year. Find more information here.
We also recommend:
TECHNICAL PAPER

Combustion Characteristics of a Spray-Guided Direct-Injection Stratified-Charge Engine with a High-Squish Piston

2005-01-1937

View Details

TECHNICAL PAPER

The Potential of Gasoline Direct Injection for Small Displacement 4-Stroke Motorcycle Applications

2004-32-0098

View Details

TECHNICAL PAPER

TSVSIM - Transient Engine Cycle Simulation Program and Its Correlation with Chassis Rolls Dynamometer Results

2000-01-1143

View Details

X