Alan Dowds takes a have a look at how this might assist save petrol-powered bikes
Honda’s electrically-supercharged V3 idea was probably the most fascinating issues proven at EICMA. Our man Dowds appears to be like at how this might assist save petrol-powered bikes
Generally in life, issues aren’t fairly what they appear. When Honda unveiled a brand new 75° V-3 engine on the Milan present, with a radical new electrical supercharger arrange, everybody rushed to take a position about how a lot energy we’d be getting, what wild superbike it could energy, and the way it might revolutionise MotoGP and WSBK racing.
However there’s one other aspect to the tech as properly – which is likely to be much more helpful to the bike world total. As a result of an electrical supercharger might simply assist bikes escape the transfer to pure battery energy, no less than within the brief and medium time period, by making small, super-efficient, hybrid powerplants that use a lot much less petrol.
First a little bit of a recap on the essential expertise. Supercharging – or compelled induction – is an effective way of enhancing the efficiency of a small engine. If you happen to can pump extra air into the combustion chamber than would usually be drawn in via the consumption ports, you possibly can then add additional gasoline, making greater explosions. That offers extra pressure on prime of the piston, growing engine torque, therefore, extra energy from a smaller capability. Smaller engines are lighter, extra compact, and have decrease ranges of friction – so once they’re ‘off-boost’ they use much less gasoline and produce decrease emissions. However on full gasoline, they can provide huge engine energy, so that you get the very best of each worlds. It’s why most trendy inside combustion-engined vehicles have shrunk in capability and variety of cylinders – three-litre sixes become two-litre fours with turbos, and four-litre V-8s grew to become twin-turbo three-litre sixes, all of them cleaner, lighter and extra gasoline environment friendly, whereas nonetheless making the large energy and torque.
Up till now, compelled induction engines have used turbochargers or superchargers. Turbos use the vitality within the engine’s exhaust to drive the compressor, whereas superchargers use a mechanical drive from the engine. Each have execs and cons: turbos want a fancy turbine and compressor system uncovered to scorching exhaust gases, including cooling and lubrication calls for, in addition to a big, costly exhaust turbo manifold which brings packaging points (they’re typically protruding the place the entrance wheel has to go). However a turbo makes use of otherwise-wasted vitality from the exhaust gasoline movement to compress the consumption cost. Superchargers are less complicated – although they want a direct drive (typically a belt) from the engine crankshaft.
This new Honda arrange provides one other dimension although. Utilizing an electrical motor to compress the consumption cost is novel expertise, solely actually seen thus far on F1 race automotive engines. There are a great deal of benefits. With a wise ECU management, the engine designer will be capable to dial in no matter consumption strain they fancy, inside the limits of the electrical motor, at any level within the rev vary. So, you gained’t be ready for a heavy turbocharger turbine and compressor wheel to speed up, or a mechanical supercharger to hurry up with the engine revs.
That might clearly carry efficiency benefits when it comes to peak energy – however the different benefit is effectivity. Having {an electrical} supercharger drive means the vitality to compress the consumption cost will come from a battery pack. That battery might be charged up regularly, as with a hybrid automotive, taking otherwise-wasted vitality when slowing down or braking, and even slightly bit whereas idling or cruising. So, whereas a mechanical supercharger robs vitality from the engine on a regular basis when it’s getting used, the electrical charger shall be extra environment friendly, solely utilizing electrical cost saved up at different instances when it must (and also you gained’t have the fixed frictional losses of a belt, pulleys, shafts, gears or chain). Matched to trendy engine administration, super-lean operating and different tweaks, this supercharged V3 might be extraordinarily gasoline environment friendly in addition to extraordinarily highly effective.
The opposite aspect of the F1 electrical supercharging is a bit trickier and doesn’t characteristic on the Honda V3 prototype proven in Milan. F1 engines additionally had a turbine wheel within the exhaust movement, like a turbocharger, however as a substitute of utilizing the vitality from that to mechanically drive a compressor, it’s linked to a small generator that produces electrical energy. That may both be used to energy a motor within the transmission so as to add direct energy – as in a hybrid automotive – or it might be used to energy the electrical supercharger, utilizing the ‘free’ vitality within the exhaust gasoline movement like a ‘digital’ turbocharger.
Put all this collectively, with some good electronics, and you would have a particularly environment friendly powerplant, with the potential for giant energy from a small engine. A 500cc petrol engine, with electrical supercharging and an exhaust turbine-powered generator, along with an electrical motor within the powertrain and a modest battery pack might produce near-1,000cc energy at full chat with all of the supercharging, turbine technology and electrical hybrid enhance. However when cruising, or round city, it could give the gasoline consumption and emissions of a 250, very like Kawasaki’s present Ninja 7 Hybrid. Make the battery pack a plug-in chargeable design and also you’ll get even greater advantages, particularly on brief runs like day by day commutes. Lengthen this expertise throughout your vary, and a agency like Honda might provide you with sub-50cc engines that carry out like a 125, 250cc engines with 500cc+ energy, and so forth.
As soon as the essential electrical supercharging applied sciences are developed, it ought to be straightforward sufficient to use them throughout a variety of equipment, giving us the efficiency all of us need, with the effectivity and clear operating important for future fashions to remain on sale.
