If you are having a hard time getting grease in (and keeping it in, or the push-on fittings in) to the swingarm bushings, it's because the Japanese standard grease zerks had no capture lip. Every grease gun you find in the U.S. has lip-grip fittings.
So, you can pull the Japanese ones out (they are just pressed in), thread the hole and install U.S. type zerks. These really help forcce the grease into the bushings and keep it there, and they don't fall back out! (I actually pushed my bike over once while trying to hold a hi-PSI grease gun against the fitting, hence this change...
).
The ones shown below were threaded straight 1/4-28 threads. You should be able to get a tap & drill set for these at Home Depot or most hardware stores.
