UMS 7-50cc CIRCLIP ROCKER ARM ( X 10 QTY / PACK)

This is the circlip rocker arm for the UMS 7-50cc engine, the seven-cylinder 50cc four-stroke radial from UMS.

The part itself is the rocker arm retaining circlip.

Why it is replaced: renewed whenever the rocker gear is disturbed, since a dislodged clip can jam the valve train. Supplied as a pack of 10, which is how these small parts are normally bought — you rarely need just one.

Fitting note: Use a new clip every time; a sprung clip can come off in service.