Although they often go unnoticed in the Harley Indian wars, Henderson motorcycles were the largest and fastest motorcycles of their time, widely favored by cops and speed demons. In 1911, America's pioneer four-cylinder motorcycle designer William G. Henderson prevailed upon his father, an automobile company VP who thought there was no future in motorcycles, for the money to build his first bike. William formed a partnership with brother Tom to open the Henderson Motorcycle Company in Detroit, and began designing the prototype for the third four-cylinder production motorcycle ever built in the USA.

The first Henderson Four rolled off the line in January 1912, and featured an innovative folding hand crank for easy starting. At 56 cubic inches, the inline four cylinder engine boasted 7 hp for the price of $325. An immediate sensation with the press, the motorcycle attracted worldwide attention, and was soon being exported overseas. Although it wasn't intended to be a racing bike, the Henderson gained even more notoriety when Carl Clancy became the first motorcyclist to circle the globe later that year. This turned out to be the first of many land speed records set by Hendersons on the punishing roads of the era.

In spite of their early successes, the Henderson brother suffered severe financial difficulties with the advent of WW I. As a result, the company was sold in 1917 to Ignaz Schwinn, famed manufacturer of bicycles, and moved to Schwinn's Excelsior production facility in Chicago. Both brothers stayed with the company, until Arthur O. Lemon stepped in to design 1920's revolutionary Model K, the first motorcycle to use full pressure lubrication. Dreaming of lighter and faster machines, William left the company to form Ace Motor Corporation, and met his untimely end while taking his Ace Sporting Solo for its first test drive.

In 1928, Schwinn hired Arthur Constantine away from Harley Davidson to become his chief engineer, and by 1929, his masterpiece, the Streamline model, aka the KJ appeared. Produced from 1929 through 1931 and boasting 57 new features, the KJ sold for $435. Among its innovations were a five main bearing crankshaft and down draft manifold. But most importantly, it was the fastest motorcycle on the road, capable of speeds in excess of 110. Incredibly smooth and powerful, the KJ quickly became the gold standard of American police departments.

As is often the case at Big Dog Garage, there's a funny story behind Jay's acquisition of this Henderson. One day, a guy in his 90s called Jay. He was in the process of getting a divorce, needed to sell his motorcycle, and wanted it to go to a good home. He had bought it in the 1940s and driven it since then. Amazingly, the head had never been taken off and the bottom never opened up, proof of the sheer reliability of the KJ. Jay fell in love with the bike, and decided to preserve it as he found it - an unrestored daily driver from a golden bygone era.