Lot 416 - 1951 BMW RS Type 253a 492cc Racing Motorcycle For Sale by Auction

This motorcycle is Lot 416 to be auctioned by Bonhams at The Autumn Stafford Sale (The Classic Motorcycle Mechanics Show) on 12 & 13 October, please see the Bonhams website for full details.

Auction Timings:
Lots 1 - 176 are to be sold from 11:00 on Saturday 12th October 2024.
Lots 201 - 429 are to be sold from 11:00 on Sunday 13th October 2024.

Public Viewing:
Available 12th & 13th October 2024 from 09:00 until 17:00, at The Stafford County Showground (The Classic Motorcycle Mechanics Show).

Lot 416

1951 BMW RS Type 253a 492cc Racing Motorcycle
Registration no.
Frame no. S252 001 (stamped to rear plunger)
Engine no. none visible (genuine works engine)
• Exceptionally rare post-war racing model
• On static display for some considerable time
• Requires recommissioning/ restoration

"Only 32 of the overhead-camshaft RS (Rennsport) engines were originally built, the last in 1953, although plenty of spares and modifications were turned out later. The RS of 1953 was scarcely impressive with its 50bhp, although it had far more useful torque and basic stability than the purebred racers of England and Italy." - LJK Setright, On Two Wheels.

When BMW-mounted Georg Meier became the first foreign winner of the Isle of Man Senior TT in 1939, it marked the pinnacle of pre-war success for a firm that, remarkably, had not built a motorcycle of its own until 1923. Originally an aero engine manufacturer, Bayerische Motoren Werke (BMW) had come into being in July 1917 when the Bayerische Fluzeugwerke (BFW) company was reorganised. BMW's engines proved their worth time and again in aerial combat in WWI, but on cessation of hostilities the firm had no option but to seek other work, hence the switch to motorcycles.

As far as competition was concerned, BMW would not be ready to challenge the British factories - which dominated international motorcycle racing - for some time, choosing instead to concentrate its efforts on speed records. Works rider Ernst Henne held the world motorcycle speed record for most of the 1930s, leaving it at 173. 57mph in 1937, a figure that would not be bettered until 1951. From 1935 onwards Henne used a supercharged (kompressor) 500cc twin, and this forced induction technology was first applied to the factory road racers that same year. BMW's spirit of innovation also extended to the racers' cycle parts: telescopic front forks were fitted from '35 and plunger rear suspension from 1937, but it was not until 1939 that it all came together in that historic Senior TT victory.

When the FIM banned superchargers from international competition after the war, BMW responded by developing a new, normally aspirated racer, albeit one based on the basic pre-war design. The first engines were effectively the pre-war type minus the 'amputated' kompressor, but these were merely interim designs pending the arrival of one developed from the start with normal aspiration in mind.

By 1956 the RS had benefited from considerable development. In 1956 BMW works rider Walter Zeller finished 4th at the Isle of Man TT, was 2nd at the Dutch TT and Belgian Grand Prix, and 3rd at the Italian round, ending the season as runner-up behind MV's John Surtees in the World Championship. Two years later privateer Dickie Dale rode an RS to 3rd place in the World Championship, beaten only by MV works riders Surtees and John Hartle.

Bonhams consulted the BMW Archive when researching this machine and the engine is a very rare factory racing unit that marks the transition from the 'amputated' kompressor motor to the RS54 model of 1952/ 53. Dating from 1951, it has the old chassis with telescopic fork and plunger rear suspension and the first version of the newly developed Type 253 engine. Type 253b from 1952 had the same engine but a new swinging-arm chassis. Unfortunately, these exceptionally rare models are barely documented.

Clearly unused for a considerable period, this BMW RS will require careful recommissioning, or potentially more extensive restoration, before further use and thus is sold strictly as viewed (the engine turns over). The fuel tank appears to be of modern construction and it should be noted that the gearbox feels loose. Prospective purchasers must satisfy themselves with regard to the condition, completeness, authenticity and compatibility of this Lot's component parts prior to bidding.

All lots are sold 'as is/ where is' and Bidders must satisfy themselves as to the provenance, condition, age, completeness and originality prior to bidding. Visit the Bonhams Motorcycles website for all pertinent auction information.