Guzzi continues air-cooled development

Published: 23 December 2001

Those who prefer the traditional sound of an air-cooled Guzzi to the Euro-conformity of a water-cooled engine will be relieved to hear that the company has not stopped development of it’s water-less unit.

In fact large portions of the engine are currently being redesigned to allow it to carry on in production well into the 21st century.

While Guzzi may be experimenting with a liquid-cooled motor (due for limited production in late 2002) Guzzi engineers have not been ignoring the old motor.

To help it beat ever tightening emission laws designers have been looking at fitting a Lambda sensor. This measures gases being expelled and adjusts the fuelling to maximise efficiency.

This system is ideally suited to Guzzis as it has to work with fuel injected bikes, something that has been on its production bikes for years.

Guzzi is also thought to be experimenting with hydraulic tappets. These are relatively common in the car world but surprisingly few bikes come with them.

Instead of the valves being opened by a sold cam follower there is an oil chamber between the camshaft and valve which operates the valve. As this chamber is fed with pressurised oil it can not come out of adjustment and retains a near zero valve clearance.

The benefits of this system include a very quiet running motor that is also relatively maintenance free. There are no shims to be adjusted and as long as the oil is changed regularly the system lasts for ages.

The only drawbacks to hydraulic tappets is the extra weight and complexity it adds to the motor and its limitations at high revs. Big-twin Guzzis are rarely required to rev high.