O.S. Engine OS22631020 Ball Bearing Compatible with 12CV-R, 15CV-RX, 12TR, CZ-11PS  [OS22631020]

Fitment guide for the O.S. ball bearing

This part is offered as a replacement bearing for the identified O.S. Engine models: 12CV-R, 15CV-RX, 12TR, and CZ-11PS. It is intended to address wear that causes play or rough rotation in the engine's internal assemblies.

Always confirm the engine model code on the case before ordering. Replace the bearing on a clean bench, following the engine's disassembly steps to remove the head and crank, and press the new bearing squarely into place using a driver that bears on the outer race so the internal balls and inner race are not stressed.

Do not allow grit or excess lubricant to contaminate the bearing during fitting. Inspect the crank for nicks, ensure correct endplay, and verify free rotation after installation. Although the bearing does not alter timing or power output, a properly seated low-friction bearing supports consistent tuning and reliable running.