Suzuki has filed a patent for what is a unique way of installing an engine in a motorcycle. While the idea is a radical one, Suzuki is not the first manufacturer to try to, literally, turn the tables on conventional engine design and installation. Italian bike building firm, Nembo, designed a bike called the 32, which sported an upside-down engine. The first prototype of this motorcycle was operational way back in 2011. However, owing to lack of funding, a production-ready Nembo 32 never saw the light of day.
Nembo experimented with an upside-down layout in an effort to aid mass centralisation – the mass of the rider along with the crankshaft (now placed at the top of the motor), reduce the radius around which most of the mass is distributed. This results in a bike that is theoretically much more nimble.
In Suzuki's case, the patent design doesn’t show a completely inverted motor, but one that has been angled forward and now carries the gearbox in the front (under the cylinder) rather than at the rear of the motor. This design seems applicable to engines with single- or inline cylinder layouts. The benefits of doing so come in the form of a shorter wheelbase while making room for a longer swingarm. This, again, improves the handling of a motorcycle.
From the patent image, it can be seen that the cylinder now runs almost horizontally, with the cylinder head perpendicular to the top of the fork. This creates more space in the front, allowing the engineers to move the front wheel backwards, resulting in the shorter wheelbase. The layout also allows for the swingarm pivot point to sit further ahead than on a conventional motorcycle, since the crankshaft is now on the upper-half of the bike.
While the design will likely undergo multiple changes before it makes its way to a production-ready model, it raises the question as to whether it will be possible for engines with multiple cylinders. For this particular layout, a larger engine will require a much wider frame, which could get in the way of steering movement. Nembo had managed to squeeze in a giant 1,814cc inline three-cylinder motor within the 32’s frame, but the Italian company had turned its engine upside-down, whereas the Suzuki design isn’t a complete 180-degree rotation of the motor. Suzuki’s patent image also doesn’t include the positions of components like the radiator and air filter box.
That said, Suzuki does have the technological and financial backing to make this design a reality and it will be intriguing to see if this ever makes it to a production bike.