Yamaha’s Built a Turbocharged Three-Cylinder Superbike

[Hugh Janus]

Yamaha’s been busy of late, this time with a new triple-cylinder turbocharged prototype. (Japanese Patent Office/)

We’ve known for a while that Yamaha’s R&D department has been working on turbocharged motorcycle projects, and now the company has revealed the first details of a prototype that further explores turbo technology. Last year Yamaha filed patent applications for a turbocharged parallel twin derived from the MT-09, but with one cylinder removed. However, the prototype is a bespoke 847cc three-cylinder turbo machine.

Tests have shown impressive power and torque numbers for the prototype, with emissions far below that of comparable normally aspirated machines. (Japanese Patent Office/)

While the 847cc capacity matches that of the 2014-2020 MT-09, the turbo bike’s engine is quite different—with a longer stroke (73mm) and smaller bore (67.5mm) to make for a relatively low-revving, high-torque design. During tests the bike hit a power peak of 180 hp at 8,500 rpm, along with a massive 130 pound-feet of torque on tap. Around 90 percent of that maximum torque turned out to be available all the way from 3,000 rpm to 7,000 rpm, easily outmuscling the V-Max’s numbers in the process. Also impressive is that this was achieved with 30 percent lower CO2 emissions than comparable normally aspirated engines and a vast reduction in carbon monoxide, NOx and hydrocarbon emissions, all coming in well under half the levels permitted by the latest Euro 5 rules being introduced in Europe from January next year.

Direct injection and variable valve timing help the engine run cleaner as well. (Japanese Patent Office/)

The turbo alone isn’t responsible for the improved emissions. The engine also features direct fuel injection, squirting gas straight into the combustion chambers rather than into the throttle bodies. The lower-revving nature of the turbo motor probably helps here, since making DI work on screaming normally aspirated motorcycle engines is known to be a tricky engineering task. Yamaha has also added variable valve timing to both the intake and exhaust camshafts, mimicking the sort of technology that’s commonplace on modern cars but has yet to make the leap to motorcycles.

Related Content: Yamaha Developing Turbocharged Twin

While the question of turbo lag has always hung over turbocharged motorcycles, with any delay in throttle response hampering the riding experience, Yamaha seems to have cracked that nut during the prototype’s development, using advanced boost-control electronics, so that during tests at 3,000 rpm in third gear it takes just over one second to reach 90 percent of peak torque.

This prototype is meant simply to showcase the turbo technology rather than serving as a template for a production model. (Yamaha/)

While the engine is a bespoke design, the prototype it’s bolted to draws heavily on MT-10 parts—using the standard production bike’s Deltabox beam frame, swingarm, fork, and even much of its bodywork, including the tank and tail unit. The side panels, which hide the turbo’s intercooler, are purpose-made for the prototype, while the water radiator hangs uncomfortably close to the ground underneath. However, bear in mind that this prototype is simply exploring turbo technology, not a design that’s destined for production in this form, or anything like it. With around 12.5 percent more power than an MT-10 and a huge 50 percent boost in peak torque, the fact that the prototype is around 44 pounds heavier than an MT-10 at 507 pounds isn’t likely to blunt its performance much either. With a purpose-made chassis to suit the engine, some of that excess weight could probably be trimmed too.

Although the prototype is well within Euro 5 emissions limits, there’s a good chance Yamaha will wait for Euro 6 rules to be set before moving forward on the project. (Japanese Patent Office/)

How far off is a turbocharged Yamaha production bike? That’s an unknown at the moment, but it’s worth noting that Kawasaki was busy filing patent applications and developing prototypes for its supercharged Ninja H2 a full five years before the production model was launched. With no firm introduction date or definite requirements set for Euro 6 emissions limits yet, it’s likely that Yamaha is biding its time until it knows where the target is before pushing ahead with this project.

Suzuki is also working on turbocharged bikes at the moment, with the Recursion parallel twin slowly edging toward production, while both Kawasaki and Honda are nailing their colors to supercharging tech. Kawasaki is clearly leading the pack with its H2 range, while Honda recently filed patents for a supercharged Africa Twin.

All the Japanese Big Four firms currently have turbo projects in the works. (Yamaha Motor Corp./)

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