Originally posted by Raw760
There are only a two [b]single points opposite of each other in the revolution, where the push or pull is not parallel to the piston's line of motion.
A line of motion or any line requires two points of reference, que no?[/b]
Let me add to or rephrase this. Referring to an in-line engine for simplicity.
The horizontal(perpendicular) position of the connecting point of the connection rod to the crank shaft (as it turns) *in relation* to the piston's vertical line of motion, has no affect of stopping vertical travel of the piston.
Only the vertical(parallel) position of this point (as well as the length of the connection rod) affects the pistons length of vertical travel and velocity(wait, sorry velocity depends on relation the two and TDC or BDC).
TDC and BDC are the extents of this motion.
As the connecting point revolves with the crank, there is no travel where the rod's push or pull is perpendicular to the piston's line of motion.. Not even TDC or BDC, these are single points.
A line of motion or any line still requires two points of reference, right?
And velocity is a measure of distance over time.
So the all pistons would not cease to have a measurable velocity until the engine stopped.