Even though off-road racing has always been synonymous with BMW Motorrad, the 450 cc takes BMW into a segment which has become very important again. It is an area where robust, powerful and ridable machines are required which can last out a whole weekend or – in the event of damage – are able to be repaired by the riders themselves. In designing the BMW G 450 X, the developers considered completely new technological solutions in relation to drive and chassis – as is absolutely characteristic of BMW.
The idea was to create the ideal package, with a concentration of masses near to the overall centre of gravity and suspension settings which can be perfectly adapted to the most diverse requirements of off-road racing. The swing arm mounting is on the same axis as the drive chain pinion (coaxial), which means that not only is there no length change of the chain on compression and rebound, it is also possible to create a longer swing arm while maintaining the same wheelbase.
The unusual frame is made of high-quality steel precision tubing. In spite of minimum use of material it has an extremely good balance between stiffness and weight. The rear frame is bolted on. The chassis elements are in line with the high standards of the class – fully adjustable Marzocchi 300 mm upside down fork at front, directly controlled progressive Öhlins spring strut with 320 mm spring clearance at rear. Mounted at a tilt, it is supported directly by the rigid main frame, so the rear frame only bears the weight of the rider.
The engine is a 450 cc DOHC 4-stroke single cylinder specially designed by BMW with dry sump lubrication. Features which have been rare in this class are petrol injection and oxygen sensor regulation. The heavily tilted cylinder position enables almost straight intake air ducting into the large-volume airbox: ideal conditions for optimum engine output set-up. The cylinder angle and fuel tank under the seat are also positive in terms of centre of gravity positioning. The position of the clutch on the crankshaft is also unique. It was possible to design it to very compact dimensions because due to the lack of gear reduction of the primary drive, it runs at engine speed and therefore has to transfer a lower level of torque. The power is transmitted from the crankshaft to the gearbox by means of an intermediate shaft complete with integrated ventilation function. An electric starter is mandatory. The performance figures of the engine are at competition level, as is the total vehicle weight. With the current team of riders and the experience gathered over the last two years, this year is clearly about one thing – winning the title.
