Three years after the success of the 1903 Single, Harley-Davidson released the Model 2, another single engine bike, with the displacement bumped up from 24.74ci (405.41cc) to 26.8ci(439.9cc). There was an option to go with the smaller wheels (26in vs. the 28in), as well as a hand crank designed into the engine. According to Conner, this was the year the nickname "Silent Gray Fellow" first appeared, though many attribute that to the 1911 Model 7D. Regardless, it's amusing to think that nowadays, one of the first things Harley riders tend to swap out is the quiet stock mufflers for something with a bit more rumble.