http://en.wikipedia.org/wiki/Evinrude_Outboard_MotorsEvinrude E-TEC was the first outboard engine technology to win the American Environmental Protection Agency 2004 Clean Air Excellence Award, which recognizes low emission levels. It is also recognized as acceptable for use by the European Union. When compared to a similar 2004 four-stroke engine, carbon monoxide emissions with Evinrude E-TEC are typically 30 to 50 percent lower; and at idle are lower by a factor of 50 to 100 times. In addition, Evinrude E-TEC emits 30 to 40 percent less total particulate matter on a weight basis than a similar “ultra-low emissions” four-stroke outboard. Furthermore, oxides of nitrogen and hydrocarbon emissions for Evinrude E-TEC are similar to, if not lower than, a four-stroke outboard. There are no oil changes with this engine, as well as no belts, and no valve or throttle linkage adjustments. This makes Evinrude E-TEC engines easier to own than comparable four-stroke engines. In addition, numerous advancements combine to create the Evinrude E-TEC quiet signature sound including an exclusive idle air bypass circuit.
you might want to educate your self a little the new two strokes are cleaner and more efficient than there 4 stroke counter parts for the same power.WhiteBlue wrote:Apart from the fact that there will be a brand new four stroke turbo formula from 2014 you also find a lot of environmental concerns against two stroke engines. Unless something fundamental changes I see practically no chance in the next decade. Two stroke engines are not fuel efficient and they have no closed lubrication circuit. The FiA will be dead against the technology.
Well, all 2-strokes work that way. The pressure inside the cylinder after the combustion is higher than in exhaust manifold so the gases go out of the cylinder.Richied76 wrote:i'm sorry but are ricardo out of there minds? do they seriouslt think an engine will evacuate exhaust gas when the piston is traveling downwards?
I think you will find Ricardo have a pretty sound idea on the workings of an IC engine.Richied76 wrote:i'm sorry but are ricardo out of there minds? do they seriouslt think an engine will evacuate exhaust gas when the piston is traveling downwards? the "concept" above is not only usless as far as actually being ablt to have two sets of differeing cam's but the bloody thing will be as efficiant as painting your house with a tooth brush!
you have that backwards. the 2 strokes were 500s the 4 strokes were 900sRatatouille wrote:The 2-stroke vrs. 4-stroke dilemma was pretty much settled in the early 2000's MotoGP. IIRC 2-stroke engines were allowed up to 1000cc and 4-stroke engines up to 500cc.
I remember the Pons Honda from Alex Barros using 2-stroke with higher CC's, while other teams including official Honda team using 4-stroke engines.
It was shown back then that the 2-stroke cylinders had much better torque but the 4-stroke offered much better power curve and above all driveability and top end speed.