Motorcycles have a long and storied history and to understand their evolution, we have to go all the way back to the very start - the late 19th century.
The first major development and attempt at widespread distribution of motorcycles took place in 1885. The invention of a bicycle-styled vehicle with a gasoline-powered engine dubbed the Petroleum Reitwagen, is purported to be the 1st motorcycle. This “motorcycle” was invented by three German men, Gottlieb Daimler, Nicolaus Otto and Wilhelm Maybach. While the Reitwagen didn’t have much to offer in the looks department, it boasted a feature that most certainly set this bike apart from the rest. The Reitwagen had two "outrigger wheels” which stabilized and supported the bike while still allowing it to turn with ease. While the outrigger wheels made it appear safer it was ultimately a poor design for handling. Still, few can argue that the Reitwagen wasn't a revolutionary and unique design that paved the road for the future of modern motorcycles.
Though the Reitwagen successfully proved that gas engines could be utilized to power vehicles, the concept was largely abandoned by inventors of the time. The idea took another 15 years to properly gestate and by about 1901, motorized bicycles grabbed the minds of industrialists and inventors alike and soon bigger brands where popping up. Triumph was already established in bicycle market in the 1880's and in 1901 began producing motorbikes, and by 1903 it was producing over 500 motorcycles a year. Other British firms were Royal Enfield, Norton, Douglas, Motorcycles and Brimingham Small Arms (BSA) who began motorbike production in 1899, 1902, 1907 and 1910, respectively. In America, Indian began production in 1901 and Harley Davidson was established two years later in 1903 and would eventually overtake Indian to become the dominant American Brand. However, it was Indian the carried the day at the beginning and by the outbreak of World War I, Indian was the largest motorcycle manufacturer in the world - producing over 20,000 bikes per year!
The Indian Motorcycle Manufacturing Company was founded by former bicycle-racers. They created the "diamond framed" Indian Single. The engine of the Single was built by an Illinois company called the Aurora Firm per Indian's specifications. This bike was available in deep blue and its production was 500 bikes in 1902. By 1913 those numbers would rise to upwards of 32,000. Indian would continue to produce more than 20,000 bikes each year.
This era saw significant innovation and experimentation, driven largely by the increasingly popular new sport: motorcycle racing. This sport created a strong incentive for companies to produce faster, tougher, and more reliable bikes. Such enhancements and better modifications would quickly find their way into the machines used by the public. For instance, Berkeley, California’s Police Chief August Vollmer is given the credit for successfully putting together the very first official police motorcycle patrol in the U.S. back in 1911. And by 1914, motorcycles were not simply engine powered bicycles, they now boasted their own different technologies, though a good majority still boasted bicycle-like concepts, such as the suspension and seats.
In 1903, the world most famous motorcycle brand was created, when a man named William Harley, partnered with brothers Walter and Arthur Davidson to launch Harley-Davidson in Milwaukee, Wisconsin. The company started in a wooden shack, which served as a sort of makeshift machine shop. Following countless false starts and unsuccessful prototypes, the men finally crafted a design that worked in 1905. They began production later that same year.
By 1909, Harley-Davidson would go on to release the V-Twin engine, the very first of its kind. The V-Twin was a dual-cylinder engine - exactly what Harley-Davidson needed to make a name in the market. During the first World War I, the United States government bought tens of thousands Harley-Davidson motorcycles to be used on the front lines of battle, propelling Harley-Davidson to a dominant position in the market. Modern variations of the V-Twin remain a crucial part of Harley-Davidson’s product line to this very day.
Many other motorcycle companies would also continue to refine and innovate throughout the era, including the Triumph Model H, aka the “Trusty Triumph.” The Triumph was one of the most popular motorcycles during the first World War, manufacturing more than 57,000. This model was among one of the first motorcycles that lacked pedals. It is generally referred to as the first “real” motorcycle.
The evolution of motorcycles was fraught with trial and error, forgotten companies recreating and innovating, but there is a direct lineage from these motorcycles to motorcycles as we know them today.