Imagine a Harley-Davidson motorcycle with an engine ... The compression ratio of 10:1 was commendable for the engine size and helped produce 2.5 horses. That was reasonably powerful for a 1960s ...

Harley-Davidson Big-Twin engines have always tended toward the upper end of their contemporary displacement ranges, which ...

But the name likely stuck due to the motorcycles' large size, roaring sound, and powerful engines. The Screamin' Eagle Stage ...