1964 BMW R69S. Photos by author.
The last BMW R69S motorcycle rolled out of the company’s factory in 1969, but on December 9-11, 2016, visitors to the IMS New York Motorcycle Show can once again witness an R69S come to life. To highlight the capabilities of its Heritage Service team, Northeast dealer Max BMW will be building a complete BMW R69S from restored parts on the floor of the Jacob Javits Convention Center.
Built from 1960 to 1969, the BMW R69S was a “gentleman’s sport bike,” capable of everything from canyon carving through high-speed runs on the Autobahn (or interstate). Powered by a 594cc horizontally-opposed, air-cooled twin rated at 42 horsepower, the 444-pound R69S boasted a top speed of 175 km/h (108 MPH), and featured an Earles fork instead of the more familiar telescopic fork.
Developed by Ernest Earles, the Earles fork was a leading link design that located the pivot point of a triangulated structure behind the front wheel. Constructed of lightweight steel tubing, the assembly used shock absorbers to connect the bottom swingarm (bolted through the hub) to the diagonal fork tubes, and ultimately, the head tube. Under heavy braking, the Earles fork front end resists diving (in fact, the front end rises slightly), and it superior lateral stability made it a good choice for use with a side car. The primary drawback, as with BMW’s later Telelever front end, was added weight and complexity.
Earles forks on a BMW R69S (F) and an R60/2 (R).
In keeping with its multi-purpose mission, the R69S could be ordered with a solo seat or with a bench seat for two-up riding, and design improvements saw the series gain stouter cylinders and a crankshaft vibration damper over its production run. Visually, however, the R69S wasn’t significantly different from the brand’s immediate postwar offerings, though this was born more of necessity than of design.
Demand for motorcycles in postwar Europe remained strong until the mid-1950s, but by the end of the decade had softened dramatically as the popularity of affordable alternatives (like the BMW Isetta and the Messerschmitt Kabinenroller) soared. In 1954, BMW sold roughly 30,000 motorcycles worldwide, but by 1957 this had fallen to less than 5,500 units, severely impacting budgets for motorcycle styling and engineering.
The R69S, then, was little more than an evolution of the earlier R69, which itself was based upon the R68, a motorcycle that dated to 1951. As the 1960s came to a close, the importance of the U.S. market became more evident to BMW, so to make the R69S more appealing a revised version, the R69US, was developed for the 1968 model year.
The most notable difference between the R69S and the R69US was the latter’s telescopic forks, a design more in line with what U.S. consumers expected. The R69US also offered consumers lighter alloy rims, a wider rear tire and (slightly) lower gearing, which traded off top speed for a bit quicker acceleration; what it didn’t offer, however, was sidecar lugs. For those preferring the original design, the Earles fork R69S remained available alongside the R69US in the American market for both 1968 and 1969.
Counting all variants, a total of 11,417 R69S models were assembled by BMW from 1960 to 1969, and the model was replaced by the larger-displacement (750cc) R75/5 for the 1970 model year. The R75/5 (and its stablemates, the R50/5 and the R60/5) featured a completely redesigned horizontally opposed twin and more contemporary styling, so it’s no exaggeration to say the success of the R69S ensured a future for BMW Motorrad.
Max BMW isn’t providing additional detail on the R69S to be built in New York, but the plan is to finish the build and complete a test ride by the third day of the show, Sunday, December 11. This latest project mirrors the company’s 2014 build of a 1975 BMW R90S motorcycle, which began with an existing frame and used as many new components as possible. The result was a “brand new” 1975 BMW R90S, assembled at a parts cost of over $46,000; no one ever said doing the improbable was cost-effective.
For additional information on the 2016 IMS New York Motorcycle Show, visit MotorcycleShows.com.
from Hemmings Daily – News for the collector car enthusiast http://ift.tt/2f6jhjN
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