Piston Rings Installation

Yes, that is correct. Lack of compression, blow by, etc...

just think of what their purpose is....to seal

"Harley-Davidson pistons use three rings to contain the compression loads and control the oil splash. The two rings closest to the crown of the piston are the compression rings. These are beveled so the expanding compression gases force the edge of the ring into tight contact with the cylinder walls. The oil control ring is comprised of three separate rings. It has a corrugated oil scraper ring sandwiched between two thin rings. "

Read more: How to Replace Rings on a Harley | eHow.com http://www.ehow.com/how_5856654_replace-rings-harley.html#ixzz2Hs8QrYU5

not if the pistons are gas ported

Yes that's true, " Pistons can be gas-ported via vertical holes in the piston deck or lateral slots in the top of the first ring groove. Gas porting allows combustion pressure to directly enter behind the top ring on the power stroke, pressuring the area behind the top ring for enhanced sealing. The ring retains normal tension for reduced friction through the rest of the four-stroke cycle."

standard set-up....

Read more: http://www.hotrod.com/techarticles/engine/hrdp_0910_piston_ring_tech/viewall.html#ixzz2HsOlh3fE

Such leakage as there is contains some oil. Staggering the ring gaps distributes the oil more evenly around the piston wall.

There is an other reason also very important. For most rings (not all ) the contact pressure at the edges is higher which leads to a higher surface wear on the line which corresponds to the piston stroke If all ring would have same position this could lead to an early wear of cylinder wall and rings! Some rings are with a variable radial thickness in order to compensate this aspect.

Piston rings rotate in service.

The alignment during assembly does not remain once the engine is running.

Before fitting the rings to the piston insert the rings into the bore and check that the end gap is correct with a feeler gauge and grind the ends if the gap is too small.

Inadequate ring gap will result in damage when the rings get hot and expand.

Top ring gap on the high pressure side[left hand side when standing at the crank handle side]

Second at 180 away etc.

If assembled with gaps aligning one would have more blow-by..compression leaking.

Rings does not/should not; Tested..will not turn on their own for the engine life-time. If rings turned you would find the gaps aligned when taking an old engine apart.

If the gaps are aligned, it will be easier for the combustion pressure to blow by the gaps and into the crankcase. If it continues for a long enough time, there could be damage to the rings and pistons.

The rings are staggered for the same reason as labyrinth seals work. The longer a fluid needs to travel from point A to B, the better the sealing effect. Therefore, the rings are staggered so that the gasses do not decrease compression. Compression equals power!

Yes, sealing goes down and both blow by and oil consumption are increased.

I made good money working for a Datsun dealer back in 1974 or 75 replacing piston rings. Nissan had subcontracted assembly of engines to a company that did not always stagger the piston ring gaps. The problem of excessive oil consumption was not discovered until after the vehicles were sold. Consequently, most of the L18 engines built by the assembly plant had to have the rings replaced by the dealerships. Although staggering the gaps without replacing the rings would have fixed the problem, Datsun required the removed rings to be sent back as proof that the work was performed.

if I'm not mistaken "Datsun" roughly translates to "business folly" so they changed to Nissan!