1961 BMW R50S
To the unknowing this 1961 R50S might look like just another BMW from the late 1950’s through the 1960’s. To those who can interpret the R series, they see that this is a 500cc bike, and the S means Sport. But what does that really mean?
The seller doesn’t give any hints, and even lists the incorrect engine size
This is a rare 1961 R50S that has been professionally restored with no expense spared. The engine was rebuilt by a professional BMW mechanic and has a new crankshaft, pistons, rods, etc.. The transmission and final drive was disassembled, inspected and re-sealed as all of the original components were in excellent condition. The frame, forks and other items are powder coated and the sheet metal was painted and hand striped by Terry Faulkner in Albermarle, NC. Terry has painted numerous AMCA Senior First motorcycles, and his work is excellent. The bike has triple matching numbers, starts and runs like new, and it has only been ridden 50 miles since is was restored.
The S can be found on the R69S which was offered as BMW sporting 600cc bike from 1960 until 1969 with 11,317 being produced. So you might be surprise that the 500cc Sport bike was only produced in 1960, 1961 and 1962 with only 1,634 units shipped. One of the reasons floating around as to why so few of the R50S built is because of catastrophic engine failures. When an engine designed for solo touring gets a bump in compression, larger carbs, as the S did, the rider is expected to turn the throttle a little more vigorously. When this happens sometimes the bottom end could not handle the extra desire by the rider. So goes the myth.
Comparing the R50/2 and the Sporting R50S visually from 10 feet, there is one major item that separates the two. The valve cover for the S is unique, and as such only offered for 3 years and 1,634 pairs. If you step a little closer, and you know what to look for, you will see the markings on the carburetors have a /26 instead of /24. With the 26mm carbs instead of the 24mm carbs, the spigot bolts into the cylinder head will be different. If you where to take the head off, and the valves out, you would be able to measure a difference in the exhaust valve stem diameter. You would also see a dome on the piston with large valve cut outs where the pedestrian R50/2 would not have.
The regular R50 and updated R50/2 were first offered from 1955 and ended production in 1969. Its final incarnation was rated at 26hp at 5800rpm, with a top speed of 87mph with 32,546 produced. The R50S was rated at 35hp at 7650rpm and a top speed of 99mph. Just comparing these numbers, you have to ask yourself why BMW stopped making the R50S. But looking at these numbers you will not be surprised at the final bid for this 1961 R50S. BB