BMW R 32
| BMW | |
|---|---|
 |
|
| R 32 | |
| Manufacturer: | BMW |
| Construction time: | from 1923 |
| Number of pieces: | |
| Previous model: | Helios motorcycle |
| Successor: | R 37 |
| Technical specifications | |
| Engine : | 2-cylinder boxer |
| Displacement : | 494 cc |
| Performance : | 6.3 kW at 3200 rpm |
| Gearbox : | 3-speed |
| Drive : | Cardan |
| Empty weight : | 122 kg (with sidecar 184 kg) kg |
| Top speed : | 95 km / h |
| Brakes : | drum |
| Tank capacity : | 14 l |
| Fuel consumption : | |
The BMW R 32 was the first motorcycle model in the history of the German manufacturer BMW .
history
The R 32 was developed by Max Friz , who took part in the ACM (Automobile Club Munich) drive “Through Bavaria's Mountains” with a prototype as early as May 1923. At the first Hindelang-Oberjoch race on September 16, 1923, BMW competed with two R 32s . On September 28, 1923, BMW presented the R 32 to the public for the first time at the German Motor Show in Berlin.
Forerunner "Helios motorcycle"
The Bayerische Flugzeugwerke developed, built and sold the Helios motorcycle from 1919 - first as a product of the "Bayerische Flugzeugwerke", then under the name "BMW" until production ended on November 10, 1923. The 1015 Helios were made from supplier parts and the first BMW -Boxer engine M 2 B 15 "Bavaria engine" , which was installed transversely here.
Concept of development
Neither component of the R 32 was new in and of itself, but the configuration set standards and brought numerous advantages that made the concept a milestone for BMW and motorcycle history. In contrast to the predecessor Helios and the manufacturers Douglas and D-Rad , the boxer engine was installed lengthways, that is, the crankshaft axis was in the direction of travel. This achieved very good cooling of the cylinders and the critical area of the exhaust valves. The very flat and in this installation position also short engine resulted in a low center of gravity, which benefited the driving characteristics. The flywheel could be combined with the dry clutch due to the directly flanged gearbox. The power transmission between the crankshaft and the gearbox was established directly without gears or chains. In contrast to the chain or belt drives of the time, the drive shaft to the rear wheel was almost completely maintenance-free and free of contamination.
With this motorcycle, BMW created the modular principle for future production series. The chassis and gearbox with the basic engine were largely identical; The differentiation for the displacement classes with 500 cm³, 600 cm³ and 750 cm³ and according to sports and touring models was implemented by changing cylinder bores, crankshafts and head or side-controlled cylinder heads and cylinders.
Sporting successes
The R 32 was used in races by private and works drivers.
Participation in the following races is documented:
- Hindelang-Oberjoch-Race 1923: two BMWs at the start, two first prizes and the best time of the day. One of the drivers was the works driver Rudolf Reich .
- Race "Around the Lausitz" 1924: Kopfnagel in class 4 (1st place), fastest time of the day.
- Race "Around Landshut" 1924: Franz Bieber in class 4 of the private drivers (1st place); Rudolf Reich in class 4 of industrial drivers (1st place); Katzl in class 4 of industrial drivers (2nd place).
With the launch of the R 37 sports model , the R 32 was assigned the role of a reliable touring motorcycle.
marketing
The price for the motorcycle in 1925, according to the BMW price list, was 2,200 Reichsmarks - lights, horn, speedometer and pillion seat were not included. Production ended in 1926 after 3090 units; The successor was the R 42 presented at the end of 1925 , which had been improved in many details and cost 700 Reichsmarks less despite the increased output - lighting system, horn and speedometer were standard equipment - and continued the success of the R 32 .
technology
engine
The engine with the label M 2 B 33 was built along the two-cylinder - Boxer - four-stroke engine with a flathead engine designed.
Development history
The forerunner M 2 B 15 , developed by foreman Martin Stolle based on the model of the engines of the English motorcycle manufacturer Douglas Motors , was the first boxer engine from BMW and was sold to Douglas Motors and Victoria in December 1920 as a "Bayern small engine" with 6.5 hp sold and also used in the own brand Helios . There it was installed transversely (i.e. with the cylinder axes in the direction of travel); In this installation position, the course of the cooling fins was technically correct. BMW specified the installation position of the engine as “lengthways” for the Helios and “across” for the R 32 . BMW referred to the cylinder axes, not the crankshaft axis, as is usually the case.
construction
The motor housing could be divided horizontally. An intermediate gear above the crankshaft drove the camshaft one level higher, which in turn drove the ignition system on the next level. This gear cascade made the engine relatively tall for a boxer engine.
The camshaft opened the valves via short roller tappets.
Carburetor
The carburetor, an in-house design by BMW, sucked in the air through the flywheel housing. The mixture quantity ("throttle slide") and mixture composition ("air slide") were set using 2 levers on the right-hand handlebar half.
ignition
A Bosch high-voltage magnet or an ignition generator were fastened to a platform above the crankshaft with a strap. The ignition was adjusted using a lever on the left half of the handlebar.
drive
transmission
The R 32 had a manual gearbox with a drive shaft on the right side of the unsprung rear wheel. The horizontally divisible gear housing was flanged to the motor housing. The input shaft of the 3-speed gearbox was driven by the single-plate dry clutch in the flywheel of the crankshaft. The output shaft drove the drive shaft via a hardy disk in direct extension. The kick starter was operated parallel to the vehicle's longitudinal axis; a bevel gear redirection was built into the gearbox housing for this purpose. This complex diversion was only given up five years later on the R 52 and R 57 .
Power transmission to the rear wheel
BMW referred to the power transmission from the gearbox to the rear wheel as a " cardan drive ", the drive shaft as a " cardan shaft " and the gearbox on the rear wheel as a "cardan housing" - technically correct it was only a shaft drive of the rear wheel, as there were no cardan joints.
landing gear
The chassis is a tubular frame without rear suspension ( rigid frame ), the front fork is a drawn short swing arm with leaf suspension . The saddle height was 72 cm. The first version did not have a front brake; later a drum brake was installed. The rear wheel had a foot-operated wedge brake that acted on its own brake rim.
Trivia
For decades, the Paris Motor Show in October 1923 was the location of the first public presentation of the BMW R 32 . This alleged fact was based on an interview with Rudolf Schleicher on the 20th anniversary of motorcycle construction at BMW. In 1977 BMW published an advertising poster with the premiere location "Paris":
“The R 32 is the first motorcycle with a double tubular steel frame and a quick-release axle. It will be the sensation of the Paris Motor Show and a model for motorcycle construction around the world. "
Targeted research in the run-up to the 75th anniversary in the library of the Deutsches Museum revealed that BMW was in Berlin as an exhibitor on September 28, 1923. At BMW France and in the Paris National Library, no reference to BMW as an exhibitor at the Paris Motor Show could be found - but neither was the exhibitor catalog from 1923 that was sought. The appropriate directory was only found in the archive of Daimler Chrysler Classic that contained no reference to BMW as an exhibitor in Paris.
See also
literature
- Udo Stünkel: BMW motorcycles typology: All series models from 1923 . Delius Klasing, Bielefeld 2008, ISBN 978-3-7688-2451-4 .
Web links
- BMW R 32. In: BMW History. BMW AG, accessed on December 9, 2015 (dossier of the BMW Group Archives).
Individual evidence
- ↑ Drive “Through Bavaria's Mountains” by the ACM, 1923. In: BMW Geschichte. BMW AG, May 5, 1923, accessed on December 9, 2015 (document in the BMW Group Archive).
- ↑ a b c d e f operating instructions for the 500 cc BMW motorcycle type R 32. In: BMW history. BMW AG, January 1924, accessed on December 9, 2015 (document in the BMW Group archive): "Enjoying nature and sports with a motorcycle."
- ↑ BMW presents the R 32, the first motorcycle from the BMW brand. In: BMW history. BMW AG, accessed on December 10, 2015 (document in the BMW Group Archive): "At the German Motor Show in Berlin (September 28 to October 7, 1923), BMW presented the R 32 to the public for the first time."
- ↑ Helios - the modern motorcycle from Bayerische Flugzeugwerke Aktiengesellschaft. In: BMW history. BMW AG, 1921, accessed on December 10, 2015 (document in the BMW Group Archive).
- ↑ Advertisement. The new BMW motorcycle "Helios". In: BMW history. BMW AG, 1922, accessed on December 10, 2015 (document in the BMW Group Archive).
- ↑ a b Helios motorcycle. In: BMW history. BMW AG, November 10, 1923, accessed on December 9, 2015 (photo in the BMW Group archive): “Helios motorcycle from Bayerische Flugzeugwerke (BFW) with BMW M 2 B 15 engine. The last Helios No. 1015 produced was November 10 1923 in front of the proud employees. "
- ^ Claus Diefenbach in a BMW R 32. In: BMW history. BMW AG, 1923, accessed on December 10, 2015 (photo in the BMW Group Archive).
- ↑ Price list No. 28 for BMW motorcycles R 32, R 39, R 37 and the sidecar S 38. In: BMW History. BMW AG, 1925, accessed on December 10, 2015 (document in the BMW Group archive): "BMW touring bike 8.5 PS"
- ↑ Udo Stünkel: BMW motorcycles typology: All series models from 1923 . Delius Klasing, Bielefeld 2008, ISBN 978-3-7688-2451-4 , p. 10-11 .
- ↑ BMW presents the R 42. In: BMW History. BMW AG, November 26, 1925, accessed on December 10, 2015 (document in the BMW Group Archive): “At the German Motor Show in Berlin (November 26 - December 6, 1925), BMW is presenting the R 42, the successor to the R 32 "
- ↑ BMW touring bike, type R 42, 500 ccm, 12 hp. In: BMW history. BMW AG, September 1926, accessed on December 10, 2015 (document in the BMW Group Archive): “The new BMW Type R 42 touring bike is the modern advancement of the Type R 32 touring bike that has been tried and tested over the past two years in multiple races and reliability rides. "
- ↑ BMW R 32 engine M 2 B 33, sectional drawing. In: BMW history. BMW AG, accessed on December 10, 2015 (document in the BMW Group archive).
- ↑ BMW M 2 B 15 "Bavaria Small Engine". In: BMW history. BMW AG, accessed on December 10, 2015 (dossier from the BMW Group Archives).
- ^ Douglas with M 2 B 15 engine. In: BMW history. BMW AG, 1920, accessed on December 10, 2015 (photo in the BMW Group Archive): "Foreman Martin Stolle (on the motorcycle) with his mechanics."
- ↑ Martin Stolle on a Victoria KR 1 with a BMW M 2 B 15 engine. In: BMW history. BMW AG, 1923, accessed on December 9, 2015 (photo in the BMW Group Archive).
- ↑ a b c "Milestone" poster. In: BMW history. BMW AG, 1977, accessed on December 10, 2015 (document in the BMW Group Archive): "1923: BMW builds the R 32, which already has the typical features that are still valid today: the transverse boxer engine and cardan drive."
- ↑ a b c Spare parts list and tables for the BMW motorcycle type R 32. In: BMW history. BMW AG, April 1924, accessed on December 10, 2015 (document in the BMW Group Archive).
- ↑ BMW M 2 B 33 engine. In: BMW history. BMW AG, 1923, accessed on December 10, 2015 (photo in the BMW Group archive): "Engine of the BMW R 32, product exempted, exploded view, disassembled"
- ↑ E. Voigt: From the belt to the cardan . In: BMW (ed.): BMW sheets . No. 17 . Munich June 1933, p. 6–8 ( PDF [accessed on December 10, 2015] in-house communications from Bayerische Motoren-Werke AG).
- ↑ BMW R 32. First version without front brake. In: BMW history. BMW AG, 1923, accessed on December 9, 2015 (photo in the BMW Group Archive).
- ↑ a b Mobile Tradition live: Appearance of the first BMW motorcycle in Berlin. In: BMW history. BMW AG, July 2003, p. 5 , accessed on January 14, 2016 (Mobile Tradition live - Edition 02 / July 2003).
| class | Type | 1920s | 1930s | 1940s | ||||||||||||||||||||
| 3 | 4th | 5 | 6th | 7th | 8th | 9 | 0 | 1 | 2 | 3 | 4th | 5 | 6th | 7th | 8th | 9 | 0 | 1 | 2 | 3 | 4th | 5 | ||
| up to 250 cm³ | Touring motorcycle | R 2 | R 20 | |||||||||||||||||||||
| R 23 | ||||||||||||||||||||||||
| Sport motorcycle | R 39 | |||||||||||||||||||||||
| up to 500 cm³ | Touring motorcycle | R 32 | R 42 | R 52 | R 4 | |||||||||||||||||||
| R 3 | R 35 | |||||||||||||||||||||||
| Sport motorcycle | R 37 | R 47 | R 57 | R 5 | R 51 | |||||||||||||||||||
| up to 750 cm³ | Touring motorcycle | R 62 | R 11 | R 12 | R 71 | |||||||||||||||||||
| R 6 | R 61 | |||||||||||||||||||||||
| Sport motorcycle | R 63 | R 16 | R 17 | R 66 | ||||||||||||||||||||
| Prototypes, racing bikes | R 7 | |||||||||||||||||||||||
| WR 750 | R 51 RS | |||||||||||||||||||||||
| Military motorcycles | R 12 | |||||||||||||||||||||||
| R 75 team | ||||||||||||||||||||||||
