Piston Ring is one of the motor cycle components, which attach around piston head in burning room. Generally, four strokes motor cycle piston ring consist of three components, those are compression rings, including top ring and second ring. The compression rings work to enlarge machine compression at compression step, as well as to prevent cylinder contact with piston to make tolerance. The function of oil ring, which is to protect lubricating oil, doesn’t come over to cylinder wall into Combustion chamber.
This research is done at compression rings (top ring) to know hardness value between piston ring of Honda Supra X which still newly and piston ring of Honda Supra X which have been used previously. Beside of hardness test, it is also done micrographic test to know micro structure type in new piston ring and also secondhand piston ring. The examination is at the room temperature.
The result of the hardness test using Rockwell test method, which diamond as an indenter, mayor load 60 kg, shows that the new piston ring has hardness number 38,2 HRC. The secondhand piston ring has hardness number 32,95 HRC. Micrographic test shows that the micro structure consists of ferrite and cemented.
Keywords: Piston ring Honda Supra X, Hardness number, Micro Structure, Tensile Strengt
