A hallmark of radical engineering, the BMW G 450 GS (0R31) is most famous for its coaxial swingarm pivot design. By aligning the swingarm pivot with the output drive sprocket, BMW engineers eliminated chain tension fluctuations throughout the suspension stroke, a feat that drastically improved traction and chain longevity in demanding off-road conditions.
| Specification | Technical Data |
|---|---|
| Production Years | 2007 – 2011 |
| Engine Oil Type | SAE 5W-40 (JASO MA2) |
| Oil Capacity | 1.0 Liter |
| Front Tire | 90/90 – 21 M/C 54R |
| Rear Tire | 140/80 – 18 M/C 70R |
| Tire Pressure (F/R) | 1.5 bar (21.8 psi) / 1.5 bar (21.8 psi) |
| Spark Plug | NGK LMAR9E-J |
| Battery Type | YTZ7S |
Technical Overview: The 0R31 Platform
The BMW G 450 GS (often associated with its G 450 X sibling) represents BMW’s ambitious entry into the lightweight enduro and adventure-sport market between 2007 and 2011. The 0R31 internal designation refers to a platform built for agility, featuring a stainless steel frame and a high-revving, fuel-injected single-cylinder engine canted forward to optimize the center of gravity.
Maintenance Essentials
Lubrication System
The G 450 GS utilizes a compact lubrication system designed for high-stress operation. It requires exactly 1.0 Liter of SAE 5W-40 oil. It is critical to use oil meeting the JASO MA2 standard to ensure the wet clutch operates without slipping, especially given the engine’s high power-to-weight ratio.
Ignition and Electrical
For optimal combustion efficiency, the NGK LMAR9E-J spark plug is specified. This long-thread plug is designed to withstand the thermal loads of a high-performance single-cylinder engine. Electrical reliability is managed by the YTZ7S battery, a compact AGM unit known for its high cold-cranking amps (CCA) relative to its size.
Chassis and Handling
The 21-inch front and 18-inch rear wheel configuration is the gold standard for off-road stability. Maintaining the tire pressure at 1.5 bar (21.8 psi) is essential for balancing grip and rim protection. Deviating significantly from these pressures can adversely affect the unique handling characteristics provided by the coaxial swingarm.
MotoSpecsLab Professional Verdict
The BMW G 450 GS (0R31) remains a niche masterpiece for enthusiasts who value unconventional engineering. While its maintenance intervals are more frequent than larger GS models, the precision of its components offers a riding experience that few other machines in the 450cc class can replicate. Proper adherence to the 5W-40 JASO MA2 oil spec and the specific NGK plug is non-negotiable for long-term reliability.