BMW 247 engine

The BMW 247 is an air-cooled flat twin motorcycle engine, also known as the "Airhead Boxer". It was used by BMW in its motorcycles from 1969 to 1995.

The /5 was introduced in 1969. The /6 was introduced in 1974. The /7 was introduced in 1977.

Before 1981 the ignition was points ignition. From 1981 it used electronic ignition, a lighter flywheel and was slower.

A number of different models were on the market:

* S: with the most famous BMW R90S R90S who was as fast as the Porsche Boxer in acceleration.
* CS: The Classic Sport, with a 1000cc engine.
* LS: 650cc sport
* ST: An 800cc road-styled GS.
* RS: Racing Sport
* RT: Road Touring
* GS: Gelände/Strasse or Gelände Sport depending on model - many times the winner of the Paris-Dakar rally.

BMW build other air cooled flat twin engines as the 248/1-type used for the R65. Before that they built side-valved and OHV engines commencing with the R32 of 1923. Perhaps the most famous was the R75, the 2WD sidecar motorcycle used by the Wehrmacht in World War II on the African and Eastern fronts.

After World War II, BMW was in a rebuilding period and did not produce any motorcycles in the Allied sector for 1945-1947 and only 59 for 1948.