It's an odd angle, designing an engine based on its effect on handling rather than just power production. That's the direction the Swedish engineers at Husaberg went when they aimed to give their open-class four-stroke the light handling of a two-stroke.
Admittedly, the Husaberg team admires the way two-stroke's handle. They wanted their bikes to have some of that flickable precision with their tractable four-stroke power. A four-stroke's comparatively sluggish handling stems from the extra weight of its more complex construction, as well as the powerful gyroscopic effect of its many rotating and reciprocating parts
Husaberg's approach to remedying this problem involved a total engine redesign, rearranging the components to centralize mass and reduce inertial influence. The final result is a flip-flopped engine, with its cylinder laid down at a 70-degree angle atop the transmission. The engineers claim this layout optimizes handling by condensing the gyroscopic forces and positioning them closer to the bike's center of gravity.
That groundbreaking design is a hit, as we found out after riding the 2009 FE450 in Greece just before the International Six Days Enduro. The FE might be the easiest 450 to ride, ever. It feels more like an insanely torquey and overly fast 250 than a big, chug-happy 450. It isn't as light and flickable as a two-stroke, but it comes closer than any open-class four-stroke has a right to. It instinctively corners and can switch lines in the blink of an eye.
The FE's quick handling is enhanced by a smooth-yet-thumpy power delivery. The old Husaberg engine feel with its deliberate stroke is still there, but it's got smoother fueling and a more stable chassis. There's linear delivery, plenty of traction and virtually none of the vibration these bikes have become known for.
Strangely, EFI was an afterthought-prompted by the ideal positioning of the airbox directly above the new cylinder's intake port. Once committed, Husaberg went all-in with the electronics, with data acquisition to record throttle position, acceleration and other fuel circuit parameters, as well as three built-in ignition maps. I was happiest with the most aggressive map, which allowed the bike to stay lower in the rpm range, where it loves to run
The WP fork is plush, sucking up every rock and root on the trail. For race-pace riding, it will likely require more compression damping and stiffer springs. The linkless WP shock is impressive, providing a full 13 inches of travel thanks to a new mount on the aluminum swingarm. Great traction, good chatter absorption and more than ample off-road bottoming resistance was the norm
I jumped on the $500 more expensive 570cc version for the last hour of the day and it felt just like the 450, only with scare-your-pants-off power. If you want a dirtbike that will easily pull your boat to the lake, I suggest ordering a 570.
In a period when dirtbike technology has been ramping up, Husaberg has pulled off a major technological and engineering coup. The FE450 is not only different, it works. Want one? Don't wait too long: Husaberg is only bringing 500 examples into the U.S. this year.