one more thought:

Eastwood company has a Speedometer cable lubricator ... a little gizmo that
fits on the end of a cable and allows a grease gun to pump grease (of some
sort) into the Zert fitting on the end of the gizmo. says it includes an
adapter for use on "other cables, such as throttle ...  Fits all cables up
to 1/2" in diameter."
part # 1693 Speedometer Cable Lubricator ..... $24.95
1-800-345-1178

i've never ordered from these folks, so i don't know if their stuff is any
good or not.

joel