Cylinder and Piston Matched Unit for 12TG - OS21413000 by O.S. Engine  [OS21413000]

12TG Replacement Cylinder and Piston Details

This matched cylinder and piston set is designated OS21413000 and fits 12TG-series RC glow engines as a service replacement. The focus is on restoring correct clearances and combustion chamber geometry rather than claiming performance gains.

Fit this assembly when you detect scoring, reduced compression, or other cylinder/piston wear. The unit is supplied to replace both parts together so mechanical tolerances return to expected ranges for 12TG engines.

Installation guidance: verify piston orientation and that the ring seats properly, transfer necessary gaskets or needle-valve shims from the removed parts, and follow your standard break-in routine. Re-check head clearance and glowplug alignment after assembly.

Effect on tuning: a new cylinder and piston will alter compression and running characteristics; re-confirm idle and mid-range needle settings during the first runs and make measured adjustments.

For workshop replacement this matched assembly supplies the components needed to recover engine compression and fitment on 12TG engines; always confirm clearances and perform a careful run-in.