I have a question on what happens to the needles of the carb, once a motor gets broken in.
I have heard some say, that as it breaks in, the carbs needles settings gets "leaner".
and others say, the needle settings are "richer".
I cannot find the answer to this question, but
I have done a significant amount of research and reading on this subject, and have made one discovery:
there seems to be a significant amount of disagreement on what is a break in procedure and what oil should be used, how the break in should be, etc...
what i did learn, is that the cylinder wall inner surface, is not a perfectly smooth surface. it is, from manufacturing, on a microscopic level a roughened surface, reason being, to help with oil lubrication/ adhesion of oil to cylinder wall.
the surface is "porous" in that there are peaks and valleys.
in the valleys, the oil can "hang out" while the ring passes by.
when the motor is brand new, the peaks are higher, due to being brand new.
as the motor breaks in, there is wear of this "peaks" and thus the seating effect of the rings onto the cylinder wall.
The catch, is that during the break in process, if the motor is allowed to over heat, there can be a glazing of the cylinder wall.
this can result in a loss of oil adhesion and thus, no lubrication, this then can result in wear of the cylinder.
ideally, a well lubricated area can result in no wear (but probably in minimal wear), if the break in process is done correctly.
and for these reasons, it is recommended that the motor be put under a light load or a normal loads, but not a high load.
the only problem, is, i cannot find where it mentions the motor becomes "rich" once broken in.
I have heard some say, that as it breaks in, the carbs needles settings gets "leaner".
and others say, the needle settings are "richer".
I cannot find the answer to this question, but
I have done a significant amount of research and reading on this subject, and have made one discovery:
there seems to be a significant amount of disagreement on what is a break in procedure and what oil should be used, how the break in should be, etc...
what i did learn, is that the cylinder wall inner surface, is not a perfectly smooth surface. it is, from manufacturing, on a microscopic level a roughened surface, reason being, to help with oil lubrication/ adhesion of oil to cylinder wall.
the surface is "porous" in that there are peaks and valleys.
in the valleys, the oil can "hang out" while the ring passes by.
when the motor is brand new, the peaks are higher, due to being brand new.
as the motor breaks in, there is wear of this "peaks" and thus the seating effect of the rings onto the cylinder wall.
The catch, is that during the break in process, if the motor is allowed to over heat, there can be a glazing of the cylinder wall.
this can result in a loss of oil adhesion and thus, no lubrication, this then can result in wear of the cylinder.
ideally, a well lubricated area can result in no wear (but probably in minimal wear), if the break in process is done correctly.
and for these reasons, it is recommended that the motor be put under a light load or a normal loads, but not a high load.
the only problem, is, i cannot find where it mentions the motor becomes "rich" once broken in.
and remember the reciprocating motion and how induction is achieved in most of our modern engines with higher crank case compression the fuel boost is equally improved putting slightly more into the combustion chamber.