Quick Info On Harley Knuckleheads Harley Knucklehead Discuss Quick Info On Harley Knuckleheads in the Classic Harley Motorcycles forums; A few folks have asked me about knucks, so here is a short piece I found on the internet that should help. They have been featured in Harley magazines since ...

[47knuck]

A few folks have asked me about knucks, so here is a short piece I found on the internet that should help.

They have been featured in Harley magazines since first introduced in 1936. Almost every Harley enthusiast is aware of the Harley knucklehead engine. If you are not familiar with the knuckle head engine, it is a Harley Davidson V-Twin engine which derived its nickname from the fact that the rocker boxes resemble two knuckles on the back of a hand closed into a fist. In 1936, the factory official named of the knuckle engine was originally "61 OHV".

To many motorcycle enthusiasts, whether classic, bobber or chopper fans the Harley Davidson brand name is synonymous with cool, powerful, quality motorcycle engines, accessories, and parts. Frequently, anyone building a classic or chopper will turn to a Harley power train because of the company's excellent reputation as well as for the prestige associated with owning a Harley V-Twin powered motorcycle.

The Harley Davidson Motorcycle Company initially introduced the knuckle head engine in 1936. Prior to 1936, Harley had manufactured overhead-valve singles but the 1936 knucklehead represented the first of the overhead valve V-Twins. The 1936 through 1940 EL models displaced 61 cubic inches. In 1941 a 74 cubic inch displacement FL version was added. These engines were more powerful than the flathead engine. Flatheads produced about 30 to 35 horsepower while the knucklehead generated 40 horses in the 61 cid and about 45 hp in the 74 cid models, offering noticeable extra punch.

The knuckle also introduced Harley's more modern recirculating oil system. This was a significant development, replacing the messy, inconvenient total loss oil setup of previous models. However, the engines were often experience oil leakage, but this was still a huge improvement over the previous designs.

It is noteworthy that the research and development phase occurred during the dark economic times of the Great Depression. It is also noteworthy that the knuckle led to the V-Twin engines which followed, even those in production today.

Today, the knuckle engine is a classic and anyone lucky enough to have a knucklehead motorcycle has a treasure of which they can be truly proud. Even as a basket case which must be completely rebuild, the knucklehead engine is a great choice for powering your classic or custom. These engines, when given proper care, can increase in value while providing you a truly classic motorcycle to enjoy.

[JayDee]

Thanks. How about some photos to make this info even more interesting? Please.

[Bargain Hunter]

Knucks are the best looking Harley engine ever designed.

[Scallywag]

My Dad always bragged about his Knucklehead, and I've got an old "colorized" photo of him sitting on it in his Navy Blues. Must have been taken sometime in late '45 or early '46 when he returned from the Pacific.

Dad passed in '74, and I have often considered restoring a knuckle in his memory, but with the new S&S Knucklehead motors available I may just build a new/old Knuckle. Looks like an antique but has modern reliability and comfort.

Any suggestions?