ScootsUSA Wrist Pin Bearing, 12mm Wrist Pin Bearing for 12mm Pin. This Wrist Pin is commonly found on the 1E40QMB/1PE40QMB 2-Stroke Minarelli JOG engine with the larger piston rod bearing on vehicles such as Vento Triton. (Inner Diameter: 12.4mm, Outer Diameter: 15.75mm) Inner Diameter: 12.4mm Outer Diameter: 15.75mm Length: 12.6mm