BMW builds the mother of all flat twins
The motivation for BMW’s upcoming R 18 supercruiser is a monster 1802cc horizontally opposed twin that will evidently generate 158Nm of torque from 3000rpm, and over 150Nm from 2000 to 4000rpm. Should be sufficient.
Over the years boxer twins from BMW have become more sophisticated but they have always had reliability and ease of maintenance as core virtues.
This new OHV unit combines four-valve technology, and dual camshafts and ignition units. It is the biggest boxer twin for motorcycle series production to date, running a 107.1mm bore and 100mm stroke. Peak power of 67kW (91bhp) arrives at 4750 rpm. Along with a sizeable flywheel mass and herculean torque it should be the very definition of grunt and smoothness in operation. The engine spins to 5750rpm off an idle of 950rpm.
The new boxer mill is air/oil cooled, has a vertically split engine housing and, along with gearbox and intake tract, weighs 111kg. The running surface of the metal cylinders is coated with NiCaSil.
In contrast to modern hydraulic valve clearance methods, this engine features one adjusting screw with a lock nut for each valve, ensuring quick and simple maintenance.
As used to be the case, this new unit uses a single-disc dry clutch with an anti-hopping function for transmitting drive to the gearbox. A reverse gear is available as an optional extra. Naturally, final drive is by shaft.
The R 18 will go into production shortly, with 1000 Euro preorders for the bobber being taken already in France.