Currently on display in the Martin Moto showroom is a 1983 Suzuki XN85 Turbo. This stunning bike, from a private collection, is a great example of the very brief “era” of forced induction bikes in the early 1980s.
In the early 1980s factory turbocharged motorcycles roamed the highways, promising the light weight and responsiveness of a middleweight, the power and performance of a liter bike, and a cost somewhere between the two. In addition to the Suzuki, Honda weighed in with it’s CX-500 Turbo in 1982 and later the 1983 CX-650 T.
Then there were the ’84-’85 Kawasaki GPz750 Turbo
and Yamaha’s XJ-650 Turbo Seca.
Marketing department promises notwithstanding, what this group actually delivered was a somewhat difficult power delivery (the dreaded “turbo lag”) as well as the weight, cost, and mechanical complexity of of much bigger bikes. Sales were, frankly, anemic and the turbo bikes ultimately screeched to a halt at this dead end on the motorcycle evolutionary path by 1985.
Now let’s jump ahead some three decades, to today. An interesting dynamic has recently surfaced in the industry. Are supercharged motorcycles coming back? Two recent “concepts,” shown in conjunction with the 43rd Tokyo Motor Show introductions certainly beg that very question.
At the Tokyo show Suzuki took the wraps off of their Recursion concept bike.
Suzuki Recursion. Tokyo Motor Show 2013.
Suzuki Recursion. Tokyo Motor Show 2013.
Looking beyond the underslung exhaust and other obvious efforts at mass centralization (has Eric Buell seen this?) we find ourselves drawn to the completely new powerplant. It’s a 588cc inline twin with, get this, an intercooled turbo system. How else to easily deliver 100+ hp and 74 lb-ft of torque at just 4500 rpm from less than 600cc? Yes, we know that a GSXR delivers similar power (and less torque) but you’ve got to spin it into the 5 digit rpm stratosphere to deliver those numbers. Fold the claimed 50-ish MPG rating and low rpm reliability into the mix, and Suzuki’s Recursion comes into its own. Two questions stand out in our mind. Has thirty years of technical progress made a new generation Turbo bike a much more viable product than we remember from the 1980s? Is Suzuki daring enough to bring something like the Recursion to the market? Stay tuned.
Not to be trumped by their friends at Suzuki, Kawasaki also got into the act at the Tokyo show. With minimal fanfare, no hardware, nor much in the way of technical detail, the “Good Times” folks went the “press release only” route with their revelation of an inline four cylinder “motorcycle-use supercharged engine.”
Supercharged Kawasaki concept engine. Tokyo Motor Show 2013.
The text of the Kawasaki release reads like this, “Kawasaki Heavy Industries, Ltd. also has a long history of developing technologies for turbine engines. The lifeblood of these turbines is their blades, which need to be able to cope with extreme heat and vibration while spinning at high speeds. Know-how from years of designing turbine engine blades was instilled in the first supercharger developed by a motorcycle manufacturer. And of course, designing a motorcycle-use supercharged engine in-house means that maximum efficiency could be pursued.” Not much here to sink one’s teeth into, right? But then consider these three facts. 1. For some time now Kawasaki has been utilizing Roots type superchargers to reliably deliver over 300 HP from it’s 1498cc Ultra 310 watercraft. 2. Rumors of a forced induction replacement for the ZX14-R Ninja have swirled throughout the industry for several years. 3. In recent years the Japanese motorcycle manufacturers have taken to showing their new engines well before the motorcycles for which they were intended. Think Yamaha 3 cylinder engine shown well in advance of the FZ-09. Draw your own conclusions and , again, stay tuned.
Do we have any insider knowledge? Do we know that a supercharged bike is on it’s way from one of the major manufacturers? Absolutely not. Nevertheless, it just seems like there is way too much chatter (and action) on the forced induction front for it to all be smoke and mirrors. While we anxiously await the next development, we’re about ready to place our bet that the answer is yes. Time will, as it always does, tell the tale.
P.S. In the meantime, if you have an interest in the older bikes, including Turbos and all the other technical marvels of the 1960s, 70s, and 80s then put the Fourth Annual Modern Classics Bike Show on your calendar for March 1, 2014. www.modernclassicsbikeshow.com