Since 2013, Suzuki has made clear indications that they are working on a turbocharged middleweight sport motorcycle. Now, intense recent patent filing activity shows not one, but two turbocharged bikes almost ready for production – and one of them will really blow the US market away in particular.
Japanese motorcycle maker Suzuki has been giving us strong indications that they are heavily invested into future models with turbocharged engines for several years now. But as the entire industry now projects moves toward a future of forced induction, it appears that Suzuki is right on the verge of releasing at least one turbo model in the very near future – a move that will put them right at the forefront of the coming motorcycle powertrain revolution.
Suzuki has been hinting at using forced induction in a motorcycle since 2013, when they released the Recursion concept at that year’s Tokyo Motorcycle Show. The Recursion used a simple turbocharged parallel-twin engine with a single overhead camshaft, and while it certainly started numerous conversations, wasn’t particularly “production-ready.” Two years later, however, at the next Tokyo show, Suzuki released the XE7, a new concept with a similar concept that was much more well-developed, including an intercooled turbocharger, dual overhead cams, and a much more compact design that fit neatly into the existing powertrain space on a motorcycle. Clearly, engineers at Suzuki had been working hard on refining the concept.
Now, another two years later, and on the eve of this year’s Tokyo Show, rapid patent activity by Suzuki on forced induction powertrains – especially focused on mass production requirements like emissions and heat management equipment – all but guarantees that Suzuki will release at least one turbocharged motorcycle in the very near future. As the age of reliable, affordable OEM forced induction rapidly approaches it’s dawn in the motorcycle market, here’s what we know about the bike that Suzuki will likely bring to market.
This is the engine from the XE7, Suzuki’s exciting turbocharged motorcycle concept released in 2015. In the last two years Suzuki has put a lot of work toward refining this concept and preparing it for production, as numerous recent patent applications indicate.
First of all, let’s talk about the engine. Undoubtedly the most exciting developments in Suzuki’s forced induction future have to do with what kind of engine they will turbocharge, and how turbocharging will be integrated into the new powertrain.
Based on the concepts and numerous patent drawings, we know the engine will be a parallel twin, and its dimensions suggest a middleweight-sized displacement somewhere around the 600cc mark. In terms of performance, OEMs are already very experienced in cranking large amounts of power out of 600ccs, but in an inline-4 configuration, which tend to come alive and flex their muscles at high RPMs.
Parallel twins, on the other hand, tend to have more low and mid-range power than inline-4s in their natural state, but the addition of forced induction would increase overall power and enhance low and midrange torque in particular. The likely result will be a powertrain that equals or exceeds the total power output of existing high-performance inline-4 engines, but delivers a massive increase in torque in the mid-range – a bike with relatively big power that is more usable across the rev range.
A patent drawing submitted by Suzuki gives a lot of indications about how Suzuki plans to pull off the turbo motorcycle concept.
But turbocharging any engine is easy – the difficult part is doing so in a way that will be usable on a vehicle, and especially a motorcycle where compact size is essential. Turbocharged engines add not only the turbine itself, but a network of pipes and hoses to direct the additional flow of both exhaust gases and extra air consumed by the engine, causing the overall powertrain size to be significantly larger than naturally aspirated counterparts. According to Suzuki’s slew of patent filings this year, it is here that Suzuki has focused their efforts, maintaining compactness in some very clever ways.
Suzui’s latest iteration shows a turbo system with its intercooler integrated into the airbox above the engine, in order to keep the entire system compactly within normal motorcycle dimensions. But the most revolutionary recent development is a solution to the ever-present issue of turbocharged engines having the turbo itself and the catalytic converter competing for space on a relatively short length of exhaust – which they did by simply combining both into a single assembly. On Suzuki’s new powertrain, the turbocharger and the catalytic converter are combined into a single unit – a remarkably intelligent way to minimize space and maximize efficiency of space on a motorcycle engine.
But because turbochargers operate by scavenging hot exhaust gases, and Suzuki’s unit will also serve as a catalytic converter – effectively a heat-retaining oven to burn off excess fuel – the entire unit will run remarkably hot, with operating temperatures of between 1200 and 1600 degrees Fahrenheit. That’s not something you want sitting between your legs!
To solve this problem, Suzuki’s most recent patents also focus heavily on the development of an elaborate heat-shielding system, to protect the rider from this intense heat. Additional patents reveal that Suzuki’s new bike will have a steel trellis design instead of a cast aluminum frame – which was proven on the Kawasaki H2, as it creates much more room for a turboed engines network of pipes and hoses – and a single sided swingarm.
But as exciting as Suzuki’s momentum toward their coming turbocharged motorcycle is, additional patent filings reveal that this is likely not going to be their only foray into forced induction. Another series of patents indicate what appears to be a large V-twin powered cruiser that will also get the turbocharging treatment in the near future.
The most brilliant of Suzuki’s turbocharging innovations is this one, a unique turbocharger and catalytic assembly in one unit. This makes the entire powertrain far more compact, condensing two separate assemblys that vie for space on the exhaust into one compact part.
According to the (admittedly simple) drawings, the cruiser Suzuki plans to turbocharge looks similar to the existing Suzuki Boulevard, a line of power cruisers which, in it’s larger configurations, sport either a big 1462cc or a massive 1783cc V-twin engine. While the smaller parallel twin-powered model appears to be more aimed at creating a combination of modern performance and efficiency, turbocharging an engine of the Boulevard’s size would result in positively massive, tire-shredding levels of power. If produced, the turbocharged V-twin cruiser will almost certainly become a “halo bike” for the American market where cruisers reign supreme, with power levels north of 200 whp being entirely possible.
With Kawasaki about to reveal yet a third supercharged motorcycle model this year, and recent patent filings revealing that Honda is also working on a supercharged V-twin powered engine with direct injection, there is no doubt that the age of forced induction motorcycles is upon us. But Suzuki appears to have gone all-in on the turbocharging route, and their very refined and well-developed concepts show every indication of materializing soon, positioning them well for the battle for forced-induction supremacy that we will surely see in the near future.
If Suzuki’s turbocharged twin-cylinder doesn’t excite you, this one better – a turbocharged V-twin cruiser outlined in recent patent filing applications. If Suzuki uses all the power turbocharging offers on one of it’s large-displacement V-twins in the Boulevard line, this will be the unquestionable new king of the hill in the power cruiser segment.