The G450X project originated with BMW Motorrad's desire to capture a portion of the 450 four-stroke enduro class from established manufacturers, including the Japanese big four and KTM.

The relatively underpowered Challenge had weighed substantially more than competitors like the KTM 640 Adventure, and its pneumatic rear suspension strut was both unadjustable for compression and rebound damping, and expensive to rebuild.

However, its narrow seat, low fuel capacity, small headlight and lack of wind protection meant this notion was questionable.

Also, with BMW already producing a variety of dedicated medium-weight dual-sport motorcycles such as the G650GS and twin-cylinder F650GS, the G450X was immediately recognizable as an enduro-only machine.

In the process of development, BMW engineers made a number of theoretical improvements on the design baseline established by Kawasaki, Yamaha, Honda, Suzuki and KTM.

The size of the engine's airbox meant that the fuel tank could not be located behind the steering headstock in typical fashion.

BMW designed an all-new 449 cm3 four-stroke single-cylinder engine utilizing double overhead camshafts with four valves per cylinder, and a balance shaft to reduce vibration.

If an electronic coding plug supplied with the motorcycle is installed, a second competition-oriented engine management map is enabled.

If the coding plug is installed in combination with BMW's G450X-specific Akrapovič competition exhaust muffler, engine power increases to approximately 51 BHP.

With the design brief specifying both low weight and the improved handling brought by a longer swingarm, the required space was liberated by moving the multi-plate clutch to the right-hand side of the crankshaft.

[3] The five-speed claw-shift transmission is integrated with the engine, and has an overall arrangement of gears, shafts and shift forks that was more compact than was typical.

BMW solved this problem using its Coaxial Traction system, with the front drive sprocket located on the same rotational axis as the swingarm pivot.

Mounting the clutch assembly on the crankshaft means the clutch rotates approximately three times faster than is typical, and the concentric location of the front drive sprocket and swingarm pivot means that the routine task of front drive sprocket replacement requires removal of the rear swingarm.

Following the end of the G450X's production run in 2010, its engine and frame formed the basis of three Husqvarna motorcycles from 2011 to 2014: the enduro-oriented TX449, the motocross-oriented TC449 and the rally raid-oriented TE449.