Unrestored Factory Flat Tracker – 1955 Harley-Davidson KR750

In America, Sport by Tim HuberLeave a Comment

Post Listing Update: This KR did not get any interest at the BIN of $22,500.


Fresh on the heels of the Great Depression, the AMA introduced what was known as “Class C” racing — an organized form of motorized two-wheeled competition created and structured to allow for a relatively low cost of entry in hopes of attracting more riders to the sport. Harley campaigned the WLDR until replacing it with the KR750 in ’52 — a motorcycle that, despite being technologically inferior on paper, nonetheless proved victorious for much of its time in use.

The result of Harley attempting to clap back at the increasingly stiff competition coming out of the UK at the time, the KR750 featured many of the (then) advanced types of components found on the Brit bikes of the day including the full fore and aft suspension, the control setups, and unit-construction powertrains. At the heart of the KR was an incredibly well developed air-cooled, 45.125ci (739.47cc), four-stroke, side-valve, V-Twin that supposedly generated as much as 57hp while weighing in at only 320lbs (dry), affording the side-valve tracker a claimed top-speed of 125mph.

When unleashed upon the world, the KR750 quickly began to dominate flat track competition, amassing a collective 13 wins — nine of which were achieved consecutively from ’54-’62 — and becoming the most successful motorcycle in America for close to two-decades until finally being replaced by the iconic XR750 which, until recently, remained Harley’s weapon of choice out on the dirt oval from ’70 onward. Like its predecessor, the KR also served as the basis for Harley’s road racing platform (the KRTT).

Though anyone could stroll into their local Harley dealer and place an order for a new KR750 (or TT), it’s estimated that only 500 or so units ever left the factory in Milwaukee. This particular 1955 example has clearly seen better days and is said to not be running; however it’s far from a complete basket case. The ad says the tracker wears a fiberglass tank, seat, and fender and that the specimen has been sitting in climate-controlled storage for the last four-and-a-half-decades. Aside from that — and the mention of the bike needing a rear sprocket — information on this example is pretty scant.

You can find this 1955 Harley-Davidson XR750 Factory Flat Track Racer for sale in Grand Junction, Colorado with a BIN price of $22,500