Maik’s Personal Brown Sugar

The Knucklehead Project

Andreas' Personal Harley-Davidson Knucklehead

Live the myth and customize your own legend!

A Harley is not just a motorcycle – it’s a way of life.

Andreas Bergerforth’s “Head of Thunderbike” prefers to travel the endless highways with this attitude towards life. The myth of unlimited freedom that surrounds the Harley fascinates a broad mass of people, whether teachers, bankers, masons or CEO. On average, a Harley-Davidson rider is old enough to hear the myth of “Harley” himself and “Born to be wild” on a record.

Ever since 1985, complete custom bikes have been built in Hamminkeln, which are mostly built on parts from their own production. To give these vehicles their own label, they are presented under the name “Thunderbike”. The former “Motorradschuppen” has become Thunderbike and thus a global company.

But what goals or wishes does a man already own almost all Harley models? Maybe a Harley like that did not belong to his private collection yet. Yes, but the new Andreas Bergerforth bike will not be any Harley. It turns into a perfect Harley Knucklehead Old School bobber in which Andreas manages to do himself.

The new (old) thunder bike was dismantled by us likely up to the last screw and was rebuilt with great attention to detail again. The Knucklehead engine was built until 1947. This engine is known as Knucklehead (“Knuckle Head”) due to its characteristic contours of the rocker arm bearing on the cylinder head. Motorcycles with these engines are today among the most sought-after vintage cars from Harley-Davidson, for which prices over 30,000 euros can be achieved (as of 2012).

  • Engine Knucklehead
  • Production Year 1936-47
  • Capacity 1.207 ccm
  • Drilling × Hub 87,3 × 100,8 mm
  • Power 48 PS
  • RPM 5.000 U/min

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You can find Thunderbike Parts and original Harley-Davidson Parts  in our online shop.

Making Of


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