1. Home
  2. Honda R&D Technical Review Vol.30 N...
  3. Development of Variable Cooling Sys...

Technical Review e-Book: Summary

Development of Variable Cooling System Aimed at Fuel Economy Improvement of Air-cooled Engine for Scooters

Article of Honda R&D Technical Review Vol.30 No.1


A variable cooling system was developed for a scooter equipped with an air-cooled, four-stroke, and single-cylinder gasoline engine. In this system, slats of the louver, located at the inlet of cooling air, are opened or closed by an oil-temperature-sensitive actuator. These slats shut off the supply of cooling air when the engine is in cold state or is driven with a low load. These operations of the slats help the engine oil temperature increase and the workload of the cooling fan decrease when the vehicle is running with a low load. With those effects, reduction of the mechanical loss is made possible. In addition, shortened warm-up time enables reduction of the injection fuel amount. As a result, fuel economy improvement of 3.3%, when driven in Urban Driving Cycle, was realized.


(1) JP, 60-066824 (1985)
(2) JP, 1760870 (1992)
(3) JP, 62-501864 (1987)

Author (organization or company)

Tomokazu KOBAYASHI(Motorcycle R&D Center)、Kazuyuki KOSEI(Motorcycle R&D Center)、Satoshi IIJIMA(Motorcycle R&D Center)

We would like to get your opinion on this research paper. (This is only applicable to registered members.)

The readers of this research paper have also selected these research papers.

Technology for Enhancing Thermal Efficiency of Gasoline Engine by Pre-chamber Jet Combustion
Article of Honda R&D Technical Review Vol.30 No.2
Development of 2.0 L Engine for New Accord Hybrid
Article of Honda R&D Technical Review Vol.30 No.1
Development of Horizontally-opposed Six-cylinder Engine for 2018 Gold Wing
Article of Honda R&D Technical Review Vol.30 No.2