Harley-Davidson motorcycles are known for their unique design and engineering choices, and one of those choices is the use of dry-sump engines. Here's why Harley-Davidson utilizes dry-sump engines:
Lubrication system: The primary reason for using a dry-sump engine in Harley-Davidson motorcycles is to ensure reliable lubrication. In a dry-sump system, the oil is stored in a separate reservoir or tank, typically located externally to the engine. From there, it is circulated through the engine using a pump. This design allows for a larger oil capacity and better oil cooling, which is particularly important for air-cooled engines like those found in Harley-Davidson motorcycles.
Oil management: Dry-sump engines offer improved oil management compared to wet-sump engines. The separate oil reservoir allows for better control over the oil supply, ensuring consistent lubrication even during extreme riding conditions, such as high speeds, aggressive cornering, or prolonged periods of idling. It helps prevent oil starvation and maintains optimal oil pressure throughout the engine.
Ground clearance: By utilizing a dry-sump system, Harley-Davidson can position the engine higher in the frame, increasing ground clearance. This design choice allows riders to navigate uneven road surfaces and speed bumps without worrying about the engine bottoming out.
Performance benefits: The dry-sump system also offers potential performance advantages. By separating the oil storage from the engine, it reduces the amount of oil that needs to be carried within the engine itself. This design can help minimize the weight and size of the engine, leading to improved power-to-weight ratios and overall performance.
Customization and aesthetics: Dry-sump systems offer flexibility in design and can be visually appealing. Harley-Davidson places great importance on the aesthetics of their motorcycles, and the external oil tank and associated lines can be customized and styled to enhance the overall look of the bike.
It's worth noting that dry-sump engines are not exclusive to Harley-Davidson motorcycles. They are also used in various high-performance and racing applications due to the advantages they offer in terms of lubrication and oil management.