YS Engine YSS1008 Piston Wrist Pin Compatible with 50ST & 56SR  [YSS1008]

Service replacement wrist pin for YS 50ST/56SR

This wrist pin serves as an aftermarket replacement for YS Engine items listed under the 50ST and 56SR service parts. It links the piston to the connecting rod and provides the axial pivot necessary for piston travel within the cylinder.

Fit this component during maintenance or full engine overhauls if the original pin shows signs of wear or if clearance has increased. Prior to assembly, check mating bores and the piston small end and follow the recommended engine disassembly and reassembly procedures.

Installation and tuning role

• Installation notes: follow the engine manual to remove the piston assembly, line up piston and rod small end, insert the wrist pin and secure with the engine-specified retainer.
• Tuning role: a properly sized wrist pin ensures correct piston alignment, limiting unwanted play that can change compression and throttle response.
• Maintenance tip: during rebuilds inspect for lateral movement and surface defects; replace the pin if any wear is present to avoid further damage to piston or rod.