The BMW R nineT Scrambler with the 1200 ccm two-cylinder opposed-twin engine.

Designed for higher speeds, the new opposed-twin engine has two chain-driven, overhead camshafts (DOHC) for each cylinder with valves actuated by extra light, high-speed roller followers. The radial arrangement of the four valves has enabled a highly compact combustion chamber design. As with the predecessor model, the mixture is ignited via two spark plugs. The previous compression ratio of 12.0:1 has also been maintained while knock control enables use of Super (plus) fuel with 95-98 RON. The nominal load capacity has been determined as 98 RON.

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The horizontal arrangement of the camshafts in the direction of travel on the new opposed-twin engine has resulted in two special technical features. Each camshaft controls one intake and exhaust valve and the cams are tapered due to the radial arrangement of the valves. Intake and exhaust control times for the two camshafts have been optimised for particularly vigorous unleashing of power in the lower and central speed range and with greater revving power at the same time.

Compared to the predecessor model, the diameters of the valve heads have been enlarged on the intake side from 36 to 39 millimetres and on the exhaust side from 31 to 33 millimetres. Valve play has been compensated for using light hemispherical shims. Opening strokes have been increased on the intake and exhaust side from 10.54 and 9.26 millimetres previously to 10.8 millimetres for a greater free valve cross-section. All this makes for an engine with a superior character that is a model of outstanding dynamics and sheer joy of revs, something it demonstrates impressively starting from even the very lowest of speeds.

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Another important development goal with the new opposed-twin engine was to further improve running smoothness using a balancing shaft. This moves compactly inside the hollow auxiliary shaft for the camshaft drive, thereby ensuring optimal smoothness and a gentle coast mode across the entire engine speed range, without diminishing the two-cylinder's typical basic character.
The previous ratio between bore hole and stroke of 101 to 73 millimetres has been maintained and thus the displacement of 1,170 cm3 too. The crankshaft and con-rod have also been retained along with their bearings while the two pistons made from cast aluminium have been redesigned in line with the change in combustion chamber conditions.
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