4-stroke vs 2-stroke ... smell

4-stroke vs 2-stroke ... smell

Post by David P. Schneid » Thu, 21 Sep 1995 04:00:00



It has puzzled me for a long time why 4-strokes smell different the 2-strokes
even when running the same fuel.  Why?  My guess is that in a 2-stroke you are
smelling some partially unburnt fuel.   A 4-stroke should burn cleaner.  Any
other ideas?  Any chemists out there?
 
 
 

4-stroke vs 2-stroke ... smell

Post by Richard Bro » Mon, 25 Sep 1995 04:00:00


I know that the fire is still burning when the port opens on a two
stroke, so I am sure some of the fuel burns at less than optimal
conditions.  I beleive that some fuel is blown through the cylinder
when the charge enters, adding raw *** and nitro to the exhaust.

While I am not sure if similar ills occur on four strokes, I suspect
that they are reduced due to the more "controlled" nature of the
four stroke timing.  The exhaust is much hotter on a four stroke,
which could make any castor in the fuel cook more.