V-Twin Panhead Harley Engine

Photographs courtesy of the Harley-Davidson Motor Company Archives.
Copyright Harley Davidson.

The Harley Davidson Panhead was a 2-cylinder, 2-valve, push-rod
operated V-Twin engine that was made in two versions, a 61 cubic inch
and 74 cubic inch version. The Panhead engine was named for its
trademark flat plate covers.

The Panhead first debuted on Harley
Davidson motorcycles in 1948, where it took the place of the
Knucklehead engine–on until 1965, when it was supplanted by the
Shovelhead engine. The Knucklehead engine had oil leakage problems and
the Panhead engine was designed to improve on that problem. This engine
had aluminum heads and a quieter, more efficient low end than its
predecessors. The Panhead also had hydraulic valve lifters, which
reduced engine noise, and reduced the overal maintenance.

When it first appeared in 1948, the Harley Davidson Panhead engine
was available on the Harley Davidson 48FL model motorcycle.  This
engine had a compression ratio of 7:1, used a Linkert M Series
carburetor, and was available as a 4-speed, 3-speed, or 3-speed with
reverse. The 1948 model was also available in Azure Blue, Flight Red,
Brilliant Black, and Police Silver (for law enforcement). This model of
motorcycle also had a rear wheel that was attached directly to the
drive chain, so that the chain rotates when the wheel does.