Equipped with the same Kymco-made single-cyinder and concentric gearbox output shaft/swingarm pivot as the BMW G450X, these new Husqvarnas are sort of an Italian supermoto based on a German dirt bike. The SMR449 and 511 are more than just slick tires and 17-inch wheels though, Husqvarna claims advantages like improved ground clearance, an improved ability to stick big jumps and better all-round traction.
The 2011 Husqvarna SMR449 is equipped with the same 449.5cc, 40bhp, 32lb/ft engine as the G450X — signified by the rakish cylinder head — while the 2011 Husqvarna SMR511 increases the bore from 98 to 101mm, the stroke remains 59.6mm on both. Engine performance for the larger version is not quoted. Those engines are also fuel-injected, equipped with electric start and hydraulic clutches. Both bikes weigh 118kg/260lbs (dry).
The idea with the concentric sprocket/swingarm pivot is to eliminate chain growth as the swingarm moves up and down. Husqvarna has dubbed this the “Coaxial Traction System,” claiming such advantages as reduced sprocket and chain wear and less frequent variation of the load on the transmission. That latter benefit is said to improve rear wheel traction while accelerating and over rough terrain, all while making gear shifts more positive. The end result, Husqvarna claims, is that the bike behaves in a more uniform, predictable manner through a wider variety of conditions, improving rideability and stability.
Another novel technical solution is the rear shock linkage mounted above the swingarm. This is claimed to improve ground clearance, make replacing the shock or linkage easier and provide more gradual absorption of large bumps. The latter is again said to improve rideability, while it should also reduce the recoil of the rear wheel when landing jumps, meaning the bike will be less likely to bounce the rider off.
It’s also worth noting the extra-long seat, which runs uninterrupted all the way from the steering stem to the rear fender, and the one-piece bodywork underneath it that’s completely free of seems, gaps or ridges that could trap clothing or otherwise hinder movement around the bike.