The Concept: An OHV + Inclined Cylinder that Changed the World of General Purpose Engines
The 3.5-hp GX110 engine and the 5-hp GX140 were released as ZE Series engines in January 1983, taking Honda's international competitors by surprise. The new engines offered all the advantages of OHV engines - namely, higher performance and better fuel economy - along with the added benefits of an inclined cylinder, such as a lower center of gravity and reduced vibration. Moreover, their compact size - 30 percent smaller than the target installation dimensions - enhanced design flexibility for the base machines in which they had been installed. For these reasons, the sales of ZE Series engines grew steadily after their official launch. Although the original target of 3 million units a year has been closely approached but not yet met, Honda's ZE models have become an important base of support for the company's power product operations.
The ZE engine's overall excellence is demonstrated by the fact that since its release manufacturers of general purpose engines around the world have adopted the OHV/inclined cylinder concept, making it the de facto standard. However, when it comes to OHV technology, every manufacturer has had an equal opportunity to apply it. Therefore, there are several reasons for Honda's dominance in that regard, one being the technological capabilities accrued through years of motorcycle and automobile development. The development staff, too, had worked tirelessly to achieve its goals. However above all, the engine's success was driven by "Hondaism," a unique set of philosophies shared by company employees, for whom customer satisfaction is the ultimate objective. They had decided to go with the OHV configuration at a time when no other manufacturer could, simply because they desired a way to please the consumer. They wanted to combine technology and real-world information in a way no one before them had.