Genuine OS factory head gasket for the OS 65AX two-stroke glow engine, in the standard 0.2mm thickness. This is the sealing shim between the cylinder liner and head — it sets the head clearance while sealing combustion pressure.

A head gasket crushes slightly in service to make its seal, so fit a fresh one whenever the head comes off — during a rebuild, after a piston ring or liner change, or when chasing a compression leak. Reusing a crushed gasket risks a poor seal, hard tuning, and overheating. Because gasket thickness sets the squish clearance, replacing like-for-like at 0.2mm keeps the engine at its factory compression setting.

Keep a spare in the field box — it's the part you'll want on hand the day the head has to come off.

Specifications

Brand: OS Engines (Japan)
Part number: 26904160
Type: Head gasket
Thickness: 0.2mm
Suits: OS 65AX