Characterization and mechanical properties analysis of three rocker arms of SOHC motorcycle engine

Abstract

This study discusses the differences of the rocker arm in the Indonesian market. Research on comparative studies among rocker arm is rarely done because it focuses more on research on rocker arm failure analysis and rocker arm shaft. The study of the rocker arm is usually for car engines, while for motorcycle engines are still rare. Indonesia is a country with a very high motorcycle population, 85 million motorcycles out of 250 million people. In the market can be found various types of rocker, for example, rocker arm original and rocker arm produced by other companies, but suitable for the motorcycle engine. The original rocker arm has a longer lifetime compared to an imitation rocker arm, but the original rocker arm is relatively more expensive. From the results of field studies, there are at least three rocker arm products are widely circulated in the market. Original rocker arm (H), compatible rocker arm 1 (K1) and compatible rocker arm 2 (K2). Rocker arm H, K1, and K2 have significant price differences. The price of rocker arm K1 is 46% of the price of H type, and the rocker arm K2 type price is 15% of H type. This raises the question, what are the differences between the three rocker arm even though it is equally compatible with motorcycle engines but has a high price difference. The study of the differences between rocker arm needs to be done as a data input to test the performance of each rocker arm. Aspects of research include aspects of geometry, density, surface roughness. The mechanical properties of rocker sleeves such as hardness on the site will also be studied including the factors that influence them such as chemical composition and material types. The study of the differences between rocker arm also needs to be done as input data to test the performance of each rocker arm. Areas studied include aspects of geometry, density, surface roughness. The mechanical properties of rocker arm such as hardness on the pad are also studied including the factors that influence them such as chemical composition and material type. From the results of the study concluded that rocker arm H, K1, and K2 have different chemical composition and geometry. Rocker arm K1 has advantages over H and K2 types on finer surface roughness aspects and better surface hardness. While rocker arm K2 has an advantage against H type on the aspects of finer surface roughness and harder surface hardness on the pad. The material of the rocker arm H is included in the AISI 5150 steel category, the K1 rocker arm is included in the AISI 5060 steel and for the rocker arm, K2 is the AISI 1080 steel.