1960's Period Modified BMW Rennsmaschine and "Cafe Racers"
The BMW twin cylinder motorcycle offerings from 1955 through 1969 consisted of 500 and 600 cc displacement motorcycles.
The overhead valve pushrod twin R50 and R60 models were "updated" in 1961 with tweaks to the frame, motor and few running bits. The "new" models subsequently became known as R50/2 and R60/2. To the casual observer they looked nearly identical. The tame, but torquey, /2s were reliable daily riders and particularly suited to the task of pulling a sidecar. With long and fairly comfy bench seats, these machines could hardly be considered "racers".
Manufactured in parallel were the "Sport" models of the day. The R69 was rolled out in 1955 as a replacement for the R68. It offered higher compression and in turn higher horsepower, as compared to the R60. Subtle changes to the R69 both internally and externally in 1961 saw the moniker transitioned to R69S.
Also beginning in 1961, there was a brief 2 year run of 500 cc sport model, the R50S. Alas, the R50S was too high strung and was plagued with reliability problems which resulted in production being halted. Thus from 1963 through 1969 the only Sport offering would be the R69S and later R69US (with telescopic forks.)
As the saying goes, the first motorcycle race began when the second motorcycle was built. Since the dawn of motorcycling, riders and racers have sought ways to make their machines faster, lighter, more reliable, etc. BMW riders are no different.
In the US, importers such as AMOL Precision of Dumont, NJ began offering sport and racing parts in the early 1950's. Aftermarket suppliers including Ernst Hoske and Schorsch Meier had catalogues full of accessories including gas tanks, hubs, race cams, carburetors, etc. Everything the gentleman racer or sporting enthusiast required.
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| Photo by John Steam (Flickr) |
1969 BMW "Zabrocky" Cafe Racer
Günter Zabrocky, a motorcycle dealer from Oberhausen in the Ruhr area of North Rhine-Westphalia, was known for his chassis tuning. Starting in 1967 he built a series of bespoke BMW's R69S machines. The custom frame was based on the Norton feather bed design, and retained the stock rear swingarm and kardan. The forks were modified in-house based on the Horex Hydra model SS. The seat and attachments were source from BSA. A total of 68 of these Cafe Racers are said to have been created.
Another interesting modified machine of the day was made by BMW employee and racer Ferdinand Kaczor. He designed and built his own frames which utilized the stock rear swingarm and thus maintained the original final drive and rear wheel. At the front, Ceriani forks and Fontana front brake. The motor was a modified stock lump. Fiberglass fairing and tank completed the look. Note the cable rear brake actuation. Rumor has it that Kaczor, for a time, had the lap record at the Nordschleife (Nurburgring). He is also famous for racing with the URS team which included collaborations with Helmut Fath and Friedl Münch.
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| Photos of Kaczor racebike from Motorrad Online |
