The so-called Quattrovalvole engine comes from the Griso/Breva series and has been optimized with modified camshafts for an improved torque curve.
Engine
The motor is an air/oil-cooled, longitudinally mounted 90° V-twin, four-stroke engine that displaces and generates rated output of at 7,500 rpm. The maximum torque of is developed at 5,800 rpm. The two cylinders have a bore of, the piston has a stroke of and a compression ratio of 11:1. Each cylinder head has an overhead chain driven camshaft that actuates the two intake and two exhaust valves. The 2-into-1 exhaust system made of stainless steel and has a three-way catalytic converter with two oxygen sensors; the emissions are well below the Euro 3 standard. The fuel tank on both the base model and the NTX variant holds, of which is reserve. The manufacturer recommends the use of unleaded gasoline with a Research Octane Number of at least 95, 90 R+M/2 in North America.
Suspension
The chassis consists of a tubular steel frame with load-bearing engine. A hydraulic 50 mm diameter upside-down fork by Marzocchi with of travel guides the front. The rear wheel is held by a single-sided swingarm with progressive linkage, which is damped by a Sachs-Boge monoshock with a progressively-acting lever system and 155 mm of travel. Power is transferred to the rear wheel via a shaft integrated into the single-sided swingarm with two joints and an anti-torque reaction support.
Brakes
The front wheel mounts dual disc brakes with cross-drilled, semi-floating 320 mm steel discs and radial-mounted four-piston calipers. At the rear wheel, a cross-drilled 282 mm disc with a dual-piston caliper is mounted. The brake lines are steel reinforced. The brake system on the latest models has standard anti-lock brakes and a switchable traction control system.
NTX differences
The NTX model has factory offroad accessories not found on the base model: hand guards, oil sump guard, aluminum panniers,, a larger windscreen and wire spoke wheels.
Critical reaction
Reviewers pegged the Stelvio as a competent competitor for other adventure-touring bikes like the BMW R1200GS and Yamaha Super Ténéré, although heavy. They noted in particular the ability of the NTX, with its high capacity fuel tank, to take riders to offroad destinations where refueling is not available.
