The
Panhead Engine
Here is
some little known but basic
information on the panhead chopper
engine:
More
history info found on PanHead
Parts.com
The
pan-head engine is Harley-Davidson's
second overhead-valve engine. This
engine was introduced in 1948. It
was quieter and cleaner than the
Knucklehead (another type of the
Harley Davidson engine) which had
been used since 1936.
The
Knucklehead was named after the
knuckle-like valve covers look
of an upside down cake pan on the
top of the engine.
The
Pan head got its name from the large
flat covers at the top of the
cylinder heads. It had a better
cooling system than the Knucklehead,
as well as other modifications that
reduced wear. This made it easier to
maintain.
Nonetheless,
the panhead didn't change much from
the knuckle. But it came equipped
with aluminum heads for more power
because the bikes were getting
heavier. Also, the heat beater was
depressed.
In
1955 Harley modified the pan head
engine by installing a more
efficient lower end (this is why the
panhead is quieter than the
knucklehead.)
Pan
head engines were also the first
v-twin to come with an electric
starting system in 1965.
About
the frames mounting these engines...
There
are several differences between the
pan and knucklehead frames, but most
of them are pretty hard to spot.
Some differences are infrequent,
like the straight front downtubes.
The knucklehead frames have straight
tubes’ while most of the rigid pan
head frames have "bowleg"
tubes.
However,
the early 1948, late’56, and ’57
pan frames were also straightbars.
The one sure way to tell the
difference is the top motor mount.
The top motormount on a knucklhead
frame is a straight-sided rectangle
tab, but the top mount on a panhead
is a triangular sort of shape.
It's
possible to fit a pan head engine
into a knucklehead frame, but it
takes some serious grindnig and
welding, and some hammering.
It
is quite well known that a lot of
bikers think that the pan head
choppers are the most beautiful
mechanical masterpieces ever created
by mankind. One of the reasons for
this statement is it's better and
quieter engine. In fact, the
appearance of the pan head chopper
is not at all so different that the
one of the knucklehead chopper.
You
can even build your own panhead
chopper, as long as you have the
resources. If you don't want to
spend a lot of money and time, you
can simply buy the panhead chopper
you like. All you have to do is to
find the bike for you and to go out
for a ride. You will surely fall in
love with the pan head chopper; no
matter if it is a Harley or any
other pan head bike.
