1939 BMW R51

1939 BMW R51 sits in the middle of BMW's late-1930s lineup, a proper mid-size shaft-driven twin built for riders who wanted real touring capability rather than a commuter bike. This is a motorcycle designed for covering distance on the roads of prewar Europe, and it does that job with a smoothness that set BMW apart from chain-driven rivals of the era. The shaft final drive means no chain to adjust or lubricate on a roadside stop, and the boxer twin's low center of gravity gives it a settled, unhurried feel at speed rather than anything sporty or aggressive. The 1939 model carried over without significant mechanical changes from the prior year — buyers comparing it to a 1938 example should focus on mileage, service history, and condition rather than spec differences. Today's buyer for a 1939 BMW R51 is typically a prewar motorcycle collector or a BMW marque specialist rather than a casual rider, someone drawn to the engineering lineage that connects this machine to postwar BMW twins, and willing to deal with the realities of sourcing parts and documentation for a machine built on the eve of a world war.