Failure Investigation of Connecting Rod on Four-Stroke Motorcycle

The purpose of this research is to examine the mechanism of connecting rod failure on a 110 cc 4-stroke motorcycle that exhibits plastic deformation at the connecting rod neck. Visual inspection, chemical composition testing, metallographic testing, hardness testing, and numerical simulation are the analytical techniques employed. The connecting rod material is classified as SAE-AISI 4140 steel based on the findings of the chemical composition test. The results of the metallographic tests revealed the presence of a martensite phase in the microstructure. The connecting rod material's average hardness value, as determined by the Vickers technique of hardness testing, is 500 HV. Similarity between the buckling failure mode, which happens when the load absorbed by the connecting rod exceeds the normal load and occurs in the vicinity of the maximum stress point, may be shown from stress analysis (von Mises) and buckling mode analysis (eigenvalue buckling). The history of riding motorcycles that have been altered by adding compression to get the required speed without taking the strength of the connecting rod components into account further supports this conclusion.