Effect of Rear Suspension Bump Stopper on Two Wheeler Main Structure Fatigue Life

The suspension system is crucial for vehicle dynamics, comfort, and durability. The suspension bump stopper is a vital element of the suspension system that controls the ending stroke of the shock, preventing harsh bottoming out. This paper aims to study the impact of the bump stopper on the fatigue life of the vehicle's main structure. Additionally, it seeks to analyze the effect of the bump stopper on suspension performance and comfort of a vehicle. The study involved recording strain, acceleration, and suspension stroke data on a rough terrain, under the same speed and payload conditions for two different bump stopper conditions: one with a new bump stopper and the other with a damaged bump stopper, and a comparative analysis was performed. The results of the study demonstrated that the bump stopper has a significant impact on fatigue life ranging from a factor of two to three. It was also found that stoppers can have very high engagement (82%) on a rough road, the damaged condition of which can cause increased compression stroke (6.4%) and increased compression velocity (36%). Thus, the study objectively underlined the role of stopper engagement in preventing bottoming and load damping. The findings provide valuable insights for improving the design and performance of suspension systems in vehicles for better durability and reliability. Keywords: Bump stopper, Fatigue Life, Rider comfort, Fracture, Main structure