Until electric cars and their associated technologies (motors, batteries, controllers etc.) become mainstream, the internal combustion engine will need to be further refined in order to meet upcoming fuel economy requirements and current emissions regulations -- while still producing the power that consumers have come to expect. HCCI is one technology currently being developed to make these goals possible, while direct injection and turbocharging are simply becoming quite common.

Ricardo has developed a new prototype engine called 2/4SIGHT which could give HCCI a run for its money. An engine equipped with this new system is capable of running on either the 2 or 4 stroke engine cycle, allowing their V6 test-bed to be downsized from 3.5 liters to 2.0 liters while making the same power output. This downsizing leads to a 27 percent reduction in fuel consumption and correspondingly lowered emissions.

Ricardo believes that their 2/4SIGHT technology will be cost effective and easy to package for vehicle use. A video of the test engine switching from 2 to 4 stroke can be seen here.


[Source: Ricardo]

A few years ago, Bajaj stopped making their Chetak and Legend scooters, and since then there has been a dinstinct lack of any steel-bodied, manual transmission, 4-stroke scooters on the market. Genuine Scooters has begun selling their Stella scooter again after a short absence and Vespa themselves re-released 500 of the PX150 model to the American market, but both of those machines feature 2-stroke engines. Bajaj made some pretty compelling claims regarding the emissions improvement of their 4-stroke engine as compared to the original 2-stroke powerplants like those used in the Stella and PX150, so scooter riders who feel the need to ride "green" machines have been forced to scour the used market or buy a newer "twist and go" style model. There are a few rumors circulating, though, which could change all of that. The Stella scooter is made in India by a company called LML, and that same company may begin creating four-stroke, steel-bodied scooters using an as yet unnamed 4-stroke motor ranging from 125cc, 150cc and even 250cc versions.

If LML does start making 4-stroke Vespa PX clones, we can foresee a huge market for them in the States. We would love to see Genuine Scooters offer these models alongside their current range of Stella scooters, keeping the vintage designs in dealer showrooms for years to come.

[Source: 2-Stroke Buzz]