Motorcyclist Comparo: Sumo Supermoto

Forget what the brochures say. These aren't supermoto bikes. Not supermoto as in supermotard, as in the French fusion of roadracing and motocross run on go-kart tracks with some dirt and a jump thrown in to keep things interesting. For the most part, they're crafty exercises in niche marketing. Naked twins dressed up to emulate the sort of thing Benny Carlson and Mark Burkhart back into corners for a living.

With the notable exception of Aprilia's SXV550 (see page 101 for more on that angry little animal), our lightest big-bore twin is nearly 200 pounds heavier than a proper supermoto racebike, and infinitely more civilized. This is a good thing, since something like Mr. Carlson's '07 AMA Supermoto Unlimited Championship-winning 550 has all the warmth and charm of a 12,000-rpm, 78-horsepower Insinkerator. Slideways fantasies notwithstanding, let's just say a real supermoto bike with lights is a bit too focused for 99.44 percent of the street-riding populace.

Meanwhile, our quartet of big twins serves up supermoto for the rest of us. More biased toward city streets and twisty back roads than the average broadband standard, they offer a sit-up alternative to the ubiquitous plastic-wrapped supersport. But BMW's HP2 Megamoto, Buell's XB12STT Super TT, Ducati's Hypermotard 1100 and KTM's 950 Supermoto R use decidedly different trajectories to hit that target. To figure out who comes the closest, we ran all four through a post-modern urban decathlon of surface streets, freeways, diabolically twisty backroads along with some fast bits, then capped it all off with a day at the racetrack. What happened? There's only one way to find out...

4th
Buell XB12STT Super TT
As with just about any Buell built over the past quarter-century, the Super TT diverges from the center of its chosen niche. Building on the basic Ulysses/Lightning Long foundation of a twin-spar frame/fuel tank carrying a 1203cc air/oil-cooled 45-degree V-twin, it's what the factory calls a blend of streetfighter agility and supermoto style. The riding position combines wide, flat, motocross-style bars with a soft, relatively broad seat and the highest footpegs of the group; legroom is tight if you're tall. We're not exactly sure what to call it, though long-legged testers came up with some intriguing definitions after an hour on the freeway. The Milwaukee pushrod twin has a personality all its own as well.

Named after an early iteration of American supermoto racing, the SuperTT trundles through the urban landscape happily enough. At least until traffic congeals and the engine gets hot enough to roast a chicken, loses interest in internal combustion and stalls at maddeningly regular intervals unless you keep the revs up. And limited steering lock enforced by the broad-shouldered frame complicates the simple U-turn-allow plenty of real estate there. The Thunderstorm mill is more like a stiff breeze below 4500 rpm anyway, which means more trips to the shifter than you might expect with 73.4 cubic inches under the hood. At 478 lbs. soaking wet, Buell's Super TT is the heftiest of the foursome, carrying 28 lbs. more than BMW's longer, taller Megamoto. Though it's never really bothersome on the street, that extra mass is more noticeable than you might expect, given the most extreme steering geometry and compact chassis dimensions of the bunch.