BMW G 450 X to arrive next month with $12,450 sticker price

The G 450 X will be released in ADR compliant trim and tips the scales at an impressively svelte 111kg dry. A claimed 52hp at 9000rpm stakes a claim that this new BMW should have what it takes to cut the mustard against the established European and Japanese enduro peerage in what is one of the most hotly contested segments of the motorcycle marketplace.

Off road sales are inexorably linked with competition success and BMW have used the highly competitive World Enduro Championship and various European Enduro Championships to develop their modern day enduro pedigree.

The 450cc machine has already been seen in action on Australian soil under the pilotage of motocross legend Joel Smets where the Belgian entertained crowds at the A4DE.

BMW are famous, or infamous depending on your point of view, for going their own way when it comes to new designs but at first glance their new design looks to follow established trends.

A conventional front suspension system consisting of 45mm inverted Marzocchi forks with 300mm spring travel. A slanted progressive Ohlins shock absorber offers 320mm of travel and is fixed directly to the swingarm.

A four-stroke single-cylinder engine along the lines of what has been par for the course in the 450cc enduro class also looks fairly much standard fare for a 450cc enduro bike.

Look closer however and a few new BMW design touches become apparent.

The engine crankcases are incredibly short. BMW fitted the wet clutch directly onto the right hand side of the reverse rotating crankshaft and the engine itself has a quite extreme forward tilt.

These two design features have allowed BMW to construct a frame where the distance between the swingarm pivot and steering head is as straight and as short as possible. There is no cradle forward of the engine which gives the appearance of the engine virtually hanging in mid-air from the upper frame mounts. The frame is made from stainless steel and weighs 8.6kg.

As the clutch assembly is mounted directly on the crankshaft it is not subjected to the torque multiplying speed reduction effects of the primary drive and thus can be significantly smaller and lighter. An intermediary shaft transfers the power from the crank to the five-speed gearbox. A compact balancer shaft is incorporated and is driven off the reverse rotating crankshaft.

A swingarm that pivots in the crankcases is certainly not new but BMW’s take on the layout is certainly very different and potentially opens up many benefits.

Not only does the swingarm attach to the frame but also directly to the engine and in a very novel twist the swingarm pivots directly through a hollow gearbox output.

This eliminates changes in chain length through the compression and rebound movements of the swingarm. This means that chain tensioning devices and routing aids can be eliminated as the required chain sag of the machine is virtually nil.

Another positive side effect is reduced stress on the chain as changes in loading through the arc of the swingarm are ruled moot. It also opens up the possibility for the chain drive to be sealed from the elements in some conditions.

Obviously the technical benefits of the design are theoretically huge and it will be interesting to see if BMW has been able to capitalise on those benefits without suffering any reliability or servicing drawbacks from the system. BMW have stated that the swingarm requires removal in order to replace the countershaft sprocket however they claim that swingarm removal on the G 450 X is a much simpler task than comparable machines. BMW claim that a competent mechanic can replace the countershaft sprocket in around 15 minutes and suggest that due to the lower wear rate of the final drive due to the lack of wheelbase change through the stroke of the rear suspension that countershaft sprockets will enjoy a longer service life than conventionally driven machines.