BMW R 69 S – One of BMW’s most sought-after Boxers

BMW R 69 WILL

With Ian Fallon

Although BMW produced a wide variety of single, twin, four and six cylinder motorcycles, the twin boxer became a trademark of BMW. Since the first R 32 in 1923, the most prized BMWs have all been flat twins, and one of the most sought after was the 600 cc R 69 S.

Produced between 1960 and 1969, the R 69 S is derived from the 1951 R 51/3 500 cc. Although the R 51/3 engine layout is similar to the engine layout of the pair. Twin overhead valves before the war but with many improvements. They include a single camshaft driven by helical cutting gears instead of the previous double camshaft design with long time chains prone to wear.

Other developments saw the alternator and alternator now housed inside redesigned engine covers but retaining the pressed-up crankshaft running on rolling bearings. However, while the engine was much improved, the general chassis was still carried over from the pre-war models. This includes a rudimentary telescopic front fork and a questionable piston rear end.

Considering BMW rose from the ashes at the end of World War II, they grew stronger in the early 1950s. For 1952, the R 67 72 x 73 mm (594 cc) and the R 68 were high performance. more than 35 hp joined the R 51/3. By the end of 1953, the number 100,000^{lame pants} post-war motorcycles left behind reconstruction works in Munich.

In 1955, the twins finally received a new chassis, which was the unusual styling of the RS 54 race car launched a year earlier. Running gear now includes wishbone front and rear suspension, with the drive shaft integrated in the rear fork legs. While swingarm rear suspension is now considered mainstream, the unusual top-link Earles fork has replaced the conventional telescopic front fork.

While providing built-in anti-stall during heavy braking, the Earles fork are actually more suitable for sidecar use, a popular alternative in the 1950s. These new twins became the R 50 500 cc. and R 69 600 cc but they also coincided with a general downturn in motorcycle sales that caused many Italian and German products to disappear altogether.

BMW also nearly went bankrupt until it succeeded with the BMW 700 in 1959. Despite the bleak times, updated two-cylinder motorcycles hit the market in 1960, one of them. is the sporty R 69 S.

Externally similar to the R 69 touring, underneath the similar exterior of the R 69 S is a reworked engine. With a compression ratio of 9.5:1 and twin 26 mm Bing carburetors, the power is 42 hp at 7,000 rpm. A timer-mounted disc engine exhaust is mounted in front of the camshaft and a larger air filter and new silencers have improved air flow.

Completing the performance specs is a closer-ratio four-speed transmission and dampers that drive hydraulically, rather than frictionally. The chassis is carried over from the R 69, with 18-inch alloy rims front and rear and 200 mm dual-shoe front brakes. Although the R 69 S had a considerable weight of 202 kg, at the time there were very few machines that could move comfortably and reliably at high speeds on the German Autobahns.

An R 69 S isn’t as agile as its British equivalent, and there are some initial problems if the engine spins too hard. But after BMW incorporated vibration dampers at the end of the crankshaft from 1963, the R 69 S will run all day with a top speed of about 175 km/h.

This is something you cannot say about the British competition. BMW has built an unrivaled reputation for reliability when Danny Liska rides his R60 from the Arctic Circle in northern Alaska to Tierra del Fuego at the tip of South America. The first person to do this on a motorcycle, in a six-month period from 1960 to 1961, Liska covered 153,000 km.

The R 69 S was also very successful in endurance races; René Maucherat and René Vasseur won the Bol d’Or 24 Hours in 1960 in Montlhéry. After winning Barcelona’s 24-hour race at Montjuich in 1959 in an R69, Peter Darvill, again teamed with Bruce Daniels, narrowly won in 1960. But with the help of factory for their R 69 S, which they successfully repeated 1959 in 1961.

This year they also won the Silverstone 1000 km race. In September 1968, Kurt Liebmann and Fred Simone won the Virginia International Circuit’s 5-hour race aboard the Amol Precision R 69 US. John Potter and William van Houten were second on a similar machine. The R 69 S also piqued BMW’s interest in off-road competition; Sebastian Nachtmann, won a gold medal at the 1960 ISDT in Bad Aussee, Austria, in an R 69 S.

Unfortunately, the conservatism of the R 69 S worked against it in the 1960s. Available only in black with white stripes (or white or red on special order), they were always expensive and exclusive. Contrary to the good looks and raw power of the British twin, the BMW is considered old-fashioned.

Instead of a small fuel tank and slim saddle, the R 69 S offers a 17 or 24 liter fuel tank, small single or large double saddle. The only modernization effort was the replacement of a new long-travel telescopic fork for the US market in 1967. However, this type of fork was not popular and was avoided by traditional BMW buyers in favor of switching to use. traditional Earles fork version.

By 1969, the market demanded a new machine, and economics dictated that the R 69 S engine, with its integrated crankshaft and gear-driven camshaft, had to be replaced with a more suitable mass production. With over 11,000 pieces produced between 1960 and 1969, the R 69 S may not be a limited production machine, but it still represents an earlier era when accountants didn’t rule over techniques. monk.

As a motorcycle with all the usual BMW qualities in terms of comfort and longevity, the R 69 S offers the best of both worlds. An outstandingly practical and usable classic, the R 69 S has earned its place as one of the most coveted postwar BMW motorcycles.

Specifications BMW R 69 WILL