The terms “Euro4” and “Euro5” have been part of the motorcycle landscape for a few years now. The stringent European emission standards have started pulling the leash on manufacturers, pushing them to become increasingly creative with their engine designs and technologies. How do you keep the performance while lowering the emissions? There’s a number of ways makers have been able to answer that question; turbochargers has been one of them. A number of manufacturers have been toying with the concept of adding forced induction to their engines which allows smaller displacements to produce more power. Yamaha is the latest player added to the turbo game.
The notion of a turbocharged motorcycle isn’t entirely new. During the 80s, Japanese manufacturers tried their hand at making turbocharged motorcycles—a stint that only lasted a few years for each of the Big Four. At the time, the turbos were much more expensive than their naturally aspirated counterparts and often enough, produced less power. Combined with unresolved cooling and lagging issues, it wasn’t long before the project was dropped. Fast forward 30 years. In 2015, Kawasaki introduced the devilish Ninja H2, equipped with a supercharger.
Now, patent filings for turbochargers are popping up, including from Kawasaki and Suzuki. The latest one is by Yamaha, published on March 20, 2019. The document shows a Yamaha MT series motorcycle fitted with a turbocharged, four stroke, parallel twin engine.
As Yamaha so succinctly explains in the document: “A straddled vehicle such as a motorcycle is required to have improved fuel consumption of the engine and an improved output of the engine. To satisfy these requirements, a turbocharger is provided and the engine displacement is reduced. The fuel consumption is improved by reducing the engine displacement. The turbocharger improves the intake efficiency. In this way, an output of the engine is increased while the fuel consumption is improved.” Euro5 much?
While it would be ludicrous to patent a turbocharged engine at this day and age, the patent focuses instead on the wastegate valve actuator that releases surplus pressure from the turbo. The patent explains that the designs suggested aims at optimizing the positioning of the actuator to increase the “degree of freedom in layout of the catalyst”. By that, Yamaha means to be able to fit a bigger catalyst (that helps control the emissions) without having to make the bike bigger.
The patent was submitted in June 2017 and took two years to be published, meaning it wouldn’t be impossible for Yamaha to have made a few strides in the meantime. A timeframe for the introduction of a prototype, let alone of a production-ready model, is hard to determine at this point. Now that the company has the go-ahead, however, maybe we can hope to see something before 2019 is over!