To identify a particular Harley-Davidson motorcycle engine, you need to know the VIN number. This number is a five-digit code, with even numbers corresponding to even production years and odd numbers corresponding to odd production years. The last two digits of the VIN will be the model year, followed by the number. Often, Harley-Davidson engine numbers are not found on older motorcycles. In this article, we’ll describe how to look up these numbers, and discuss when and why you need to change the number on your motorcycle.
Date ranges for the different types of early overhead valve motors
The Revolution Max 1250T motorcycle features variable valve timing, a feature common in cars but not in motorcycles. The VVT technology came from Ducati and Honda, who introduced the system in their Diavels and Multistradas. Harley never used VVT before. The V2 engine features two overhead cams per cylinder and variable valve timing. Here are some important date ranges for the different types of early Harley overhead valve motors.
The Harley-Davidson Knucklehead motorcycle was first produced with an overhead valve. It was better suited for performance, achieving about 40 horsepower. Its 61-inch capacity was a significant upgrade from the flathead design. In 1941, Harley introduced the iconic 74-c.i. (1200cc) Knucklehead motorcycle. It quickly became one of the most popular Harleys of its day, accounting for more than half of the company’s total sales.
Date ranges for the different types of late overhead valve motors
When Harley-Davidson first began testing its new overhead-valve motorcycles in the 1930s, they were using a race-inspired design that was not practical for the street. These bikes lacked a return oil line from the rockerbox, and the oil leaked. Harley-Davidson tried to address this problem, and eventually started using a standard design that incorporated a rockerbox.
In 1931, Harley-Davidson had originally planned to use the single-overhead-valve design, but the Great Depression delayed development. The company began developing its own overhead-valve V-twin in 1932 and waited until 1941 to make it commercially available. It took five years to develop, but its development was an impressive step in motorcycle technology. Harley-Davidson eventually began offering a 74-ci. (1200cc) model, and the 61-ci. Knuckleheads remained in production until 1947.
The Revolution Max 1250T features variable valve timing. Variable valve timing was a feature common in cars, but Harley had never used it before. However, as time went on, the Harley flathead developed into a competitive motor, and the motorcycle’s power output was comparable to that of its F-head rival. The motorcycles were heavier, and the flathead models reached faster top speeds.
Date ranges for the various gearbox numbers
If you are planning to restore a vintage motorcycle, you should first learn about the different date ranges for the various Harley engine numbers. These numbers were assigned on Harley motorcycles at the time they were manufactured and are important for identifying the model. The production numbers of Harley motorcycles were always 1000. Therefore, the first EL panhead motorcycle coming off the production line in 1948 would be 48EL1001.
The VIN of a Harley motorcycle is composed of a five-digit production code, which is followed by a number. Even numbers refer to the production years while the odd numbers correspond to the odd ones. The years 0 to nine correspond to the years after 1969. However, after 1980, Harley motorcycles are manufactured with model year in the last two digits. The model number will be followed by the year.
Changing the production number of a Harley-Davidson engine
If you want to identify a bike’s model and year, you can change the production number of its engine. Harley-Davidsons had production numbers that started with 1000 until 1961. The first EL panhead off the production line would be 48EL1001, while the production numbers for bikes from 1960 to 1969 began with odd numbers. In the case of the EL panhead, the model year is the first two digits of the VIN, followed by a number.
Before 1979, the engine’s VIN was stamped on the frame and the motorcycle’s frame. However, the two parts of the engine were not identical. This is because the engine number was a different number than the frame. As of 1979, the engine’s production number was a 10 digit numerical ID, and it was important that the VIN number match with the frame’s VIN.