 | |
| Manufacturer | BMW |
|---|---|
| Production | 1935-1942 |
| Assembly | Munich, Germany |
| Predecessor | R11 |
| Class | boxer |
| Engine | Two-cylinder boxer 745cm³ - 18 hp at 3400 rev / min (20 hp at 4000 rev / min in the version with two carburetors) |
| Bore / stroke | 78 mm |
| Compression ratio | 5.2: 1 |
| Top speed | 110 km (68 mi) - 120 km (75 mi)[1][2] |
| Power | 18 hp (13 kW)[1] |
| Ignition type | Magneto or battery ignition |
| Transmission | Manual |
| Tires | 3.50 x 19 |
| Dimensions |
L: 210 cm (83 in) W: 90 cm (35 in) H: 94 cm (37 in) |
| Fuel capacity | 14 litres |
| Fuel consumption | 3.5-4L (every 100km)[1] |
| Related | R17 |
The BMW R12 is a pre-World War II motorcycle that was produced by the German car manufacturing company BMW. The motorbike was first presented and developed in 1935.[3] A total of 36,000 motorcycles were built by 1942.
History[]
On 14 February 1935, BMW presented the R12 together with the BMW R17 on the German Automobile Exhibition in Berlin for the first time, being a direct successor to the BMW R11.[4] This and the R17 were the first in the world being produced with hydraulically damped telescopic forks.[5] By 1942, the total number of BMW R12 motorcycles manufactured was 36,000.[2] For military purposes, the Einvergasermotor was only available for the R12.[6]
Description[]
BMW R12 Motor engine
Engine[]
The engine with the designation M 56 S 6 or 212 was a mounted twin-cylinder boxer - four-stroke engine with a Flathead engine designed.[1] The BMW R12 with two carburetors uses a battery ignition, while R12's with a Einvergasermotor use a magneto ignition, capable of working independently from the battery.[7]
Drive[]
The BMW R12 had a claw-switched four-speed manual gearbox, which was placed on the tank and spiral. The drive shaft was on the right side of the motorcycle, placed near the rear wheel.[7] The power transmission that was located from the gearbox and extending to the rear wheel was known as a drive shaft, according to BMW.[8]
Suspension and brakes[]
Rear-wheel driving was redesigned, with a fixed through axle, making the tyres interchangeable.[7] Caradan joints was formerly used for the R12, but all wheels were instead equipped with drum brake.[7]
Specifications[]
| Characteristics | R 12 with a carburetor[1] | R 12 with two carburetors [2] |
|---|---|---|
| Drilling | 78 mm | |
| Stroke | 78 mm | |
| Capacity | 745 cm³ | |
| Compression ratio | 5,2 : 1 | |
| Performance | 18 hp (13 kW) | 20 hp (15 kW) |
| Top speed | 110 km/h | 120 km/h |
| Tare | 162 kg | |
| Fuel capacity | 14 Liter | |
Surviving motorcycles[]
One example of a surviving BMW R12 motorcycle can be found in the Museum of Military History in Vienna, still bearing its original camouflage.[9]
References[]
- ↑ 1.0 1.1 1.2 1.3 1.4 "BMW R 12 Einvergaser" (in German). BMW Archive Group. http://bmw-grouparchiv.de/1/webmill.php?id=158078&ditem=49855&lin=detail&foldertype=all&foldergroup=irc. Retrieved 3 March 2015.
- ↑ 2.0 2.1 2.2 "BMW R 12 Zweivergaser." (in German). BMW Group Archive. http://bmw-grouparchiv.de/2/webmill.php?id=158078&ditem=49856&lin=detail&foldertype=all&foldergroup=irc. Retrieved 3 March 2015.
- ↑ "BMW R 12 Schnittzeichnung der Telegabel" (in German). BMW Group Archive. http://bmw-grouparchiv.de/1/webmill.php?id=158078&ditem=4533&lin=detail&foldertype=all&foldergroup=irc. Retrieved 3 March 2015.
- ↑ "BMW präsentiert bei den Modellen R 12 und R 17 die weltweit erste hydraulische Teleskopgabel" (in German). BMW Archive Group. http://bmw-grouparchiv.de/1/webmill.php?id=158078&ditem=35344&lin=detail&foldertype=all&foldergroup=irc. Retrieved 3 March 2015.
- ↑ Setright, L. J. K. (1977). Bahnstormer: The story of BMW Motor cycles. Transport Bookman Publications. p. 47. ISBN 0-85184-021-3.
- ↑ Zeyen, Wolfgang; Leek, Jan (2004). BMW: die Motorräder seit 1923 (1. Auflage ed.). Stuttgart: Motorbuch Verlag. pp. 71–88. ISBN 3-613-02401-2.
- ↑ 7.0 7.1 7.2 7.3 BMW AG (February 1935) (in German). The changes to the BMW 1935 machines (5 ed.). Munich: House releases of Bayerische Motoren Werke AG. pp. 12–15.
- ↑ BMW AG (May 1935). List of spare parts for BMW motorcycles type R 12 (750 cc touring model) / type R 17 (750 cc sports model). BMW Archive Group. p. 97.
- ↑ Rauchensteiner, Manfried (2000) (in German). Das Heeresgeschichtliche Museum in Wien. Graz: Styria. p. 92. ISBN 978-3222128349.
External links[]
 |
Wikimedia Commons has media related to BMW 12. |
The original article can be found at BMW R12 and the edit history here.