Dual Plugs to clean up 2st emmissions?

[Fark]

Manufacturers have done this on 4 stroke automotive cars for yeras... and BMW has adopted it on its "boxer" motorcycle motor.

My question is this: could an extra plug placed in the combustion chamber clean it up?  Even if fired a moment after the primary plug?

And also... what if it were placed in the expansion chamber, or even the stinger, fired at a strategic moment.

What about a plug placed aft of a valve placed after the expansion chamber to clean up the hydrocarbons (raw gas)?

 

[cujet]

Yes, additonal plugs can help reduce pollution on a 2 stroke. With one of the big problems being unburned hydrocarbons, anything done to ensure complete combustion will help. However, most of the problem lies in the classic 2t design with the raw gasses going right out the exhaust port.

Chris

 

[Guaryzzzpode]

I think it would not help, as the unburned fuel does not come from unburned mixture in the combustion chamber, but from fresh mixture coming in from the crankcase to the combustion chamber and "accidentaly" escaping through the exhaust port due to the design of two stroke engines.

 

[Kawierider]

what if you put the plug near the exhaust port (read above it towards that side fo the head) in theory, when sparked the flame front would keep the mixture in the cylinder.....if it is sparked early, like the plugs in the new Hemi, then it would stop the intake early......maybe enough to stop the flow of gases out of the exhaust port.
Does this make sense ?
Tim

 

[Can Can Kev]

if you put a plug near the exsaust port most likely u would have a small flame comming out of the exsaust dunno if that would matter or not but doesnt sound good, i think the best way to cut down on emmissions on a 2 cycle engine is taking the stratocharged weedeater/ chain saw technology and applying it to our large dirtbike engines....

 

[bedell99]

There was a great thread a while back on the Honda EXP-2. The clean burning 2-stroke, that used a rotary type exhaust valve, to clean up emissions. The new CR250 engine is based on that design. I will do a search to try to find the thread. As for the dual plug theory, my old Nissan pickup truck had it and it seems to make sense, especially for a 2-stroke, but what I gather is that manufacturers design simplicity and having another spark plug might complicate things for home mechanic's (Jetting, expense, electrical, etc.) While in a 4-stoke application(especially in cars) maintence isn't an issue(there hardley isn't any) so a dual plug design would work.

Erik

 

[bedell99]

Click: http://www.dirtrider.net/forums3/showthread.php?threadid=15894&highlight=honda+clean

For the thread on the honda EXP-2

Erik