Bonneville America Forums Forums Off Topic Discussion Forums Lounge The Six-Stroke Engine

http://www.damninteresting.com/?p=467#more-467

Under the hood of almost all modern automobiles there sits a four-stroke internal combustion engine (ICE). Though the efficiency of the design has been improved upon significantly in the intervening years, the basic concept is the same today as that used by the first practical four-stroke engine built in the 1870s. During every cycle in a typical car engine, each piston moves up and down twice in the chamber, resulting in four total strokes… one of which is the power stroke that provides the torque to move the vehicle. But the automotive industry may soon be revolutionized by a new six-stroke design which adds a second power stroke, resulting in a much more efficient and less polluting alternative.

In a traditional ICE cycle, 1) the fuel/air valves open as the piston moves down, which draws air and fuel into the chamber; 2) the valves close as the piston moves back up, putting the air/fuel mixture under pressure; 3) the mixture is then ignited, causing a small explosion which forces the piston back down, which turns the crank and provides the torque; and finally 4) the exhaust valves open as the piston moves back up once again, pushing the byproducts of the fuel explosion out of the chamber. This leaves the piston back in its starting position, ready for another cycle. This process is repeated thousands of times per minute.

The clever new six-stroke design was developed by 75-year-old mechanic and tinkerer Bruce Crower, a veteran of the racing industry and a the owner of a company which produces high-performance cams and other engine parts. He had long been trying to devise a way to harness the waste heat energy of combustion engines, and one day in 2004 he awoke with an idea which he immediately set to work designing and machining. He modified a single-cylinder engine on his workbench to use the new design, and after fabricating the parts and assembling the powerplant, he poured in some gas and yanked the starter rope. His prototype worked.

His addition to the ICE design is simple in principle, yet a stroke of genius. After the exhaust cycles out of the chamber, rather than squirting more fuel and air into the chamber, his design injects ordinary water. Inside the extremely hot chamber, the water immediately turns to steam– expanding to 1600 times its volume– which forces the piston down for a second power stroke. Another exhaust cycle pushes the steam out of the chamber, and then the six-stroke cycle begins again.

Besides providing power, this water injection cycle cools the engine from within, making an engine's heavy radiator, coolant, and fans obsolete. Despite its lack of a conventional liquid cooling system, his bench engine is only warm to the touch while it is running.

Veeeeeery interesting. Now where are we going to put a water tank on our bikes?

I see someone else finally found damninteresting.com. I'm running out of exclusive sources for obscure stuff.

Here's a link to another revolutionary engine idea: The split cycle engine.

And while you're at it.... mighty engine looks small enuff for a bike...

Jan

That "Mighty Engine" is pretty cool.

There seems to be a revolution on the rise for new internal combustion engines. Hopefully some car, truck or motorcycle manufacturer will give some of these ideas a chance.

I was reading somewhere recently about the Wanlkel Rotory (I keep thinking it was in the last Popular Mechanics) and how it was around for quite a while before Mazda gave it a go.

Soren

Don't forget the Norton Commander rotaries (and their F1 race bikes) and the Suzuki RE-5 and DKW and the Van Veen of the 1980's...rotary engined bikes have been around for some time so there is a precedent out there for new engine concepts in bikes....

Jan

6 , 7 whatever it takes.