Kyle, it is a four in line.
Overhead cam , driven by a shaft through the generator ( The thing in front of the engine.)
At that time an overhard cam was un herd of on motorcycles.
So was the type of front fork suspension, which all bikes have now.
BMW and Nimbus developed it at the same time and both were sure they were the first.
In 1938 the Nimbus was totally ahead of the rest.
Unfortunately, because of the Danish tax system that pretty much kept foreign motorcycles out after WW2, Nimbus didn't keep up with the times, so in 1956 they went bust.
Overhead cam , driven by a shaft through the generator ( The thing in front of the engine.)
At that time an overhard cam was un herd of on motorcycles.
So was the type of front fork suspension, which all bikes have now.
BMW and Nimbus developed it at the same time and both were sure they were the first.
In 1938 the Nimbus was totally ahead of the rest.
Unfortunately, because of the Danish tax system that pretty much kept foreign motorcycles out after WW2, Nimbus didn't keep up with the times, so in 1956 they went bust.