Yamaha Motor Co., Ltd. 823-11635-00-00 Piston Assembly

The Yamaha 823-11635-00-00 Piston Assembly is a genuine Yamaha engine piston designed for small‑engine piston-and-cylinder systems in vintage snowmobiles, where it compresses the air‑fuel charge and transfers combustion force to the cylinder bore. It is commonly used in Yamaha GP292, SM292, and GS292 models and is a key part during repair or rebuild to restore proper compression and operating tolerances. Fabricated from cast aluminum alloy for heat resistance and durability, this piston is available in oversize variants (for example 0.25 mm O/S) to restore cylinder tolerances after wear. This OEM replacement part is replaced by 823-11635-01-00 and is commonly encountered alongside other Yamaha replacements like 820-11635-00-00 and 335-11635-00-00.