BMW's new range of 650 singles

Highly stable lightweight frame made of steel and aluminium.

The particularly light frame is the same on all three models in the G 650 X series and is made up of four highly stable modules: The welded main frame made of steel profile sections, aluminium castings bolted on to the main frame around the swing arm mounting point, the aluminium lower section holding the engine in position, the forged aluminium auxiliary frame serving to take up spring strut forces, and the aluminium frame bolted on at the rear.

With its appropriate use of materials specifically chosen at each point and tailored precisely to load requirements, this concept makes a significant contribution to the minimisation of overall weight – which is precisely why the various models weigh a mere 156 kg/344 lb (Xchallenge, the lightest model) to 160 kg/353 lb (Xcountry, the heaviest model) with a full tank according to the DIN standard.

The intelligent mix of materials on the frame offers a number of other benefits: The aluminium castings around the swing arm mounting point the rider is bound to touch with his boots are eloxy-plated to prevent any such contact from leaving behind unwanted marks. At the same time the swing arm mounting point has been modified in its configuration, the swing arm now pivoting exclusively on the main frame and not on the engine block, and being positioned relatively close to the pinion.

This not only serves to provide even faster drivetrain response, but also reduces the tolerance (less slackness) of the drive chain.

Light rear frame and lower section made of aluminium.

The rear frame is bolted on to the main frame, allowing easy and low-cost replacement in the event of damage. To make the rear frame resistant to even the highest loads, high-strength aluminium forgings are welded into the ends of the eloxy-plated aluminium frame tubes bolted on to the main frame. The lower frame section holding the power unit at the front boasts the same very special lightweight technology.

Double swing arm made of cast light alloy.

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