2017 KTM 690 Duke

Two decades ago, the original Duke was nothing short of revolutionary. KTMs first single-cylinder street bike grew into a cult classic, adding extreme fun to a raw and radical concept. In 2017, the fully revised 690 DUKE stays faithful to its ancestors ways, but adds future-proof refinements: impressive smoothness, sophisticated electronics, improved ergonomics and a good old power boost over last years model. This firmly cements the worlds strongest single-cylinder production motorcycle at the cutting edge of engineering. Speaking of which: carving corners has never been more fun, thanks to its revised fork offset. Long live the Duke!

• ENGINE

The brilliant LC4 showcases twenty-four carats of fun. From the trademark 690 cm thumper, the engineers have now extracted a whopping 73 hp (54 kW) and 74 Nm of torque, making light work of the equally lightweight 690 Duke. How it happened? They completely reworked the cylinder head, inserted a new, ultra light and extremely strong piston and connection rod, rerouted the air intake through a resonator chamber and provided the crankshaft with sleeve bearings. As a result, the powerband is a thousand rpm wider, which means an even more uniform power delivery, especially in the mid to high rev range. Twin ignition featuring plug-selective mapping, rock solid but featherweight internals and optimized intake and exhaust systems cultivate this massive mono to be as strong as it is smooth, assisted by an advanced ride-by-wire system, which guarantees great refinement as well as low fuel consumption and emission figures. Youre green, while theyre green with envy. And you havent even begun mentioning upmarket goodies like a standard slipper clutch.

• NEW CYLINDER HEAD

Inside the cylinder head, the exhaust valves are actuated by roller rockers while the camshaft powers the intake valves. Therefore, the valve timings can be controlled with far greater accuracy. The result is more peak power over a broader rev range. Win-win!

• SECOND BALANCER

In a free-revving firecracker like this, you want to smooth things out a bit. Thats why the LC4 serves a bonus balancer shaft, nipping annoying vibrations in the bud.

• ENGINE MANAGEMENT

The electronic engine management system lives to make the LC4 shine. Twin ignition with individual mappings for each spark plug ensures that your precious fuel is always burned to perfection, irrespective of load and engine speed. And then there is genuine ride-by-wire, in other words: Electronically controlled throttle valve actuation without any mechanical linkage. Youd be forgiven for thinking it runs on cream. Whipped cream, that is.

• FRAME AND SWINGARM

The 9 kg tubular trellis frame made from chrome-molybdenum steel and the equally lightweight, smoking hot swingarm, die-cast in aluminum, impress with extreme levels of torsional stiffness, providing the 148.5 kg Duke with excellent tracking stability and a continuous flow of information to the rider. Triple clamps lower the fork offset, which underlines this characteristic even further. Youll notice.

• SUSPENSION

The upside-down fork on the Duke (with a 43 mm diameter) and pivot-arm articulated pressurized-gas monoshock, both by WP, excel with flawless tuning and a broad spectrum of use for all demands, from relaxed cruising to hammering around on closed circuits. The options are limitless, and so is your lean angle.

• BRAKES

The Dukes extremely powerful, precise and easily applied Brembo brakes impress with outstanding controllability. At the front wheel, a radially-mounted, four-piston, fixed brake caliper bites onto a floating 320 mm disc.