Besides the fact that you couldn't put it on the piston without the split, it allows for expansion.
There are compression ring and oil control ring
The lowest ring is the oil ring
The DNJ ring spec. information, printed on each compression ring (located next to the piston ring gap), is installed facing the top of the piston for both the top (#1) and middle (#2) compression piston ring slots. The oil control ring can be installed just like any other oil control ring in the bottom (#3) piston ring slot.
The DNJ ring spec. information, printed on each compression ring (located next to the piston ring gap), is installed facing the top of the piston for both the top (#1) and middle (#2) compression piston ring slots. The oil control ring can be installed just like any other oil control ring in the bottom (#3) piston ring slot.
The compression ring will have a dot or indentation marking the top of the ring .
oil control ring
Normal piston have 2 compression rings and a 3 piece oil ring. Some aftermarket rings have a 2 piece zero-zap second compression ring to reduce blow-by.
compression rings.. while the bottom ring is known as oil ring .
The split or gap in a piston ring is called the ring end gap. It allows for the ring to expand and contract with changes in temperature during engine operation, ensuring a proper seal against the cylinder wall.
Generally in grooves near the top of the piston. The compression rings, near the top and the oil rings at the bottom of the top. The ring gaps are staggered.
Prevents wear on the pistin and reduces compression loss
If you only use one piston ring on 80cc bike engine, the compression ration will be reduced.