BMW R69S 1967
Note the two fins on the rocker cover - this is the easiest way to identify the S models, as the R50/2 and R60/2 have many fins. Otherwise, all four /2 and S models are very similar. The R60US has teledraulic forks, rather than Earles.
More information at Motorcycles of the 20th Century
BMW R69S 600cc