Combustion engines with an odd number of cylinders are not unheard of but are not particularly common, either. Honda‘s just trotted out an interesting one: A V3, so, two pistons on one side and one on the other, with an electric compressor that’s effectively a turbocharger driven consistently by electricity instead of exhaust gas.
Usually, when you hear about an odd-cylinder engine, its pistons are in a straight row, like with a Volvo five-cylinder or a Triumph Triple inline three-cylinder engine. This one’s a V—the first Honda V3 we’ve heard of in a few decades.
The big motor vehicle technology show in America right now is SEMA in Las Vegas. But over in Europe, eyes are on the Milan Motorcycle Shows (Official Name: International Motorcycle and Accessories Exhibition aka EICMA). This Honda V3 engine concept was announced there.
It looks like the main advantage of an engine design like this is that it allows for a bump in displacement without much widening—it’s fairly skinny, despite Honda’s stating that it’s “being newly developed for larger displacement machines.” That could translate to combining better handling and bike manageability with bigger power.
The design is water-cooled, with the pistons angled at 75 degrees.
The electrical compressor is also interesting. It’s a little air-squeezing snail, just like a turbocharger. But instead of being spun up by exhaust gas, it’s powered by electricity to “control compression of the intake air irrespective of engine rpm, meaning that high-response torque can be delivered even from lower rpm,” according to Honda. The company also says this is the first time such a thing’s been shown on a motorcycle.
You can’t get something for nothing, so there’d be some power draw to make that work. But it would make exhaust plumbing easier than a traditional turbo setup. Apparently, it doesn’t need an intercooler here, either.
This is not the first-ever V3 engine. In fact, Honda had one in production on the NS400R, an extremely cool bike from the mid-’80s that I just learned about while writing this post. I’ve never seen one of these two-stroke three-cylinder sport bikes in my life, but it’s pretty sweet-looking. They weren’t around all that long though, so here’s hoping Honda’s next three-cylinder concept bears out a little better.
Honda indicated that “development will continue towards mass production” on this new three-banger idea, so we may see it on the road in the not-too-distant future. I’ll be very interested to hear what it sounds like.
Got any three-cylinder experience? Drop the author a line at andrew.collins@thedrive.com.