The secrets of the Husqvarna Norden 901 engine

The engine of the Husqvarna Norden 901 it is the parallel twin-cylinder KTM LC8c, identical in configuration to the one that equips the 890 Adventure – only the clutch and alternator covers change, those of the Husky have the House logo. It is about a unit of modern design and light weight: 53.4 kg without oil, but including all “accessory” components (starter motor, throttle bodies, cooling circuit). It is powered through 46mm diameter Dellorto ride by wire throttles.

The cylinder head has a double camshaft, both driven directly by the chain. The trees are composite: lighter, according to the House, than those made from a single piece. The cams operate the valves (made of steel) via finger rockers with DLC coating. The inlet valves have a diameter of 37 mm, those of the exhaust 30 mm. Ignition is operated by one spark plug per cylinder. It features two shafts to reduce vibrations: one is located in the cylinder head and the other in the front of the crankcase, in front of the crankshaft. To contain the masses in reciprocating motion there are forged pistons, pins and roller cages particularly light, connecting rods of reduced length. The separation between the connecting rod cap and the half-head is obtained by fracture, the fixing screws are clamped.

The crankshaft is monolithic and forged. The crank pins are offset from each other by 75 ° as on the V2 of the House, so as to have a similar sound and delivery: the bursts are one after 435 ° and the next after another 285 °. The stroke of the pistons, which have 90.7 mm of bore, is 68.8 mm, for a displacement of 889 cc. The compression ratio is 13.5: 1. The maximum declared power is 105 HP at 8,000 rpm, the maximum torque of 100 Nm at 6,500 rpm. The base opens in a horizontal plane. It is made by die-casting with a process that allows you to accurately control the thicknesses. The cylinder block has an open deck structure.

Lubrication is (obviously) forced. The crankcase is semi dry; the oil sump, under the engine, is separated from the crank chamber, from which the lubricant is evacuated with a recovery pump that also takes care of the gearbox and the clutch. The oil temperature is kept under control by means of a water / oil heat exchanger. The cable-operated clutch is slipper and has a mechanism to reduce the effort required on the lever. The gearbox is six-speed, two-way electronic. The coupons are expected every year or every 15,000 km.