HISTORY: THE BOXER & THE TYPE 247
BMW’s boxer twin is seriously old, its DNA
can be traced all the way back to 1923, when –
looking for alternative employment outside
of the military sector, banned in Germany by
way of losing WWI – BMW took a portable
industrial engine and slotted it into a bike
chassis. The R32 was in all fairness rather good,
it being a lightweight 486cc and with aluminium
alloy cylinders and unit construction (engine
and gearbox as one) it made 8.5hp – and a
heady 59mph of raw speed. The engine had
in fact appeared in an earlier motorcycle, the
Helios, with the cylinders placed fore and aft
but it was BMW’s Max Friz who turned it 90º
to the correct orientation.
The type 247 emerged in 1968, a proper topto-bottom
(or left-to-right) makeover of the
old R32 concept by a new man at BMW, Hans-
Gunther von der Marwitz, an engineer who’d
been headhunted from Porsche. H-GvdM
brought all his car experience to bear,
comprehensively overhauling the boxer by
spec’ing a one-piece forged crank in car-type
plain bearings while moving the camshaft
below the crank (and making it chain driven)
and attaching the four-speed transmission via
a car-type single plate dry clutch (that clutch
only replaced by a wet multi-plate type this
year, some 44 years later). H-GvdM then
dispensed with some of BMW’s favoured tech,
like Earles forks, and modernised the rolling
chassis – adopting a double-loop frame not
unlike the Norton Featherbed – to create the
modern /5 ‘slash-five’ roadster that was
available in 600cc and 750cc variants. The type
247 engines, now known as ‘airheads’ – being all
air-cooled – would power R-series BMWs right
through to 1996 when they were at last given
a significant refresh (with oil-cooled heads, to
become known as ‘oilheads’).
68 KIWI RIDER