Sometimes ideas are too ahead of their time and get forgotten over the years. In 1978, Kawasaki released the Z1R TC, the first motorcycle to use a Turbocharged engine which gave it noticeably more power that other engines of the same size. However, after a brief love affair that lasted into the early ’80s, Japanese bike manufacturers turned their backs on the technology.

Now at this year’s Tokyo Motor Show from 23 November to 1 December, Suzuki is looking to bring it back with their new concept Recursion sports motorcycle which promises to go back and rectify all the problems that dogged turbocharged bikes of the past.

■  What’s turbo?

Just to make sure everyone’s on the same page, here’s a brief explanation of a turbocharger. A combustion engine generates power by igniting a mixture of air and fuel. The more mixture you have in the engine, the more power you get. This means that the power is limited to the size of the engine, often measured in cubic centimeters (cc) for motorcycles.

A turbocharger works to compress the air which allows more of it to enter the engine and thus produces more power. For example, Suzuki’s Recursion bike has a 588cc 2-cylinder long stroke engine, but thanks to its intercooled turbocharger it can produce 30% more power (100hp/8,000rpm and 10.2kgm/4,500rpm to be exact) than other bikes with the same engines according to specs.

As an added bonus, a turbocharger is powered by reusing the vehicle’s own exhaust which makes for better fuel efficiency and cleaner overall exhaust. Turbochargers are widely used on cars, trucks, planes, ships, and trains. However, motorcycles never quite took on the technology.

■  What took so long?

Turbochargers were gaining in popularity for domestic cars in the ’60s and ’70s and eventually were tried out on motorcycles as well. Honda, Yamaha, Suzuki, and Kawasaki all released models which tried to take advantage of turbo power.

However, when using a turbo charger there is a slight delay for the effect to kick in. Because turbo requires exhaust to work the engine first has to produce some at its regular efficiency before the boost can be felt. This effect known as “turbo lag” is fine for vehicles that move linearly with a steady, gradual acceleration, but motorcycles require very delicate control of acceleration, especially when cornering.

Moreover, the lightweight body and instability of a two-wheeled vehicle made the overall experience of turbo lag more of a clunky nuisance than a benefit to the rider. So, for three decades since, very little has been seen in terms of a turbocharged bike.

■  Recursion

In the nearly 30 years that motorcycle makers have appeared to shun turbo power, many developments have been made by engineers to reduce the effects of turbo lag. In addition, the proliferation of the fuel injected engine has helped to increase the precision of accelerating, making turbo lag even less of an issue.

Suzuki has been one of those automakers developing turbo for their line of compact and mini cars, and now they think it might be time to bring it back to motorcycles. With a body composed of lightweight aluminum and carbon monocoque rear frame the Recursion weighs in at just 174kg (383lbs). In addition to the 30% improvement to output compared to other same-sized engines, it also boasts a 50% improvement in fuel efficiency thanks to the revival of turbo.

Suzuki hopes that in the not-too-distant future this old-yet-new combination will offer riders all the perks of a turbocharged engine without the loss to handling for a purely enjoyable riding experience even in the tight, winding streets of the city.

Source: Yahoo! Japan News (Japanese)
Top Image: Suzuki
Inset Images: YouTube – Car@nifty

If you’d like to learn more about the Recursion then hop on down to the 43rd Tokyo Motor Show and see one in person.

Information

The 43rd Tokyo Motor Show 2013
Tokyo Big Sight
3-11-1 Ariake, Koto-ku, Tokyo
Open to General Public: Saturday, 23 November to Sunday, 1 December
Mon-Sat – 10am to 8pm
Sun – 10am to 6pm
Adults – 1,500 yen (US$15)
High School Students – 500 yen ($5)
Junior High and Younger – free