Yamaha YZF-R125, MT-125, XSR125, and R125 owners with valve train ticking, tapping noise, or power loss caused by a worn rocker arm. Yamaha R125 2019 125 R125. Yamaha R125 2020 125 R125. The Valve Rocker Arm Assy is a pivoting lever in the engine's valve train that transfers motion from the camshaft lobe to open the valve against its spring.
