Yes, it is a radial roller bearing.
Yes, it is lubricated by splash from the gearbox lube.
No, don't snug up the cable to control noises. A snug cable is what leads to premature failure of this bearing. It is supposed to be a 'momentary' application. That is it is only under pressure when you pull the hand lever.
Pulling the swingarm would be a lot easier than pulling the battery tray.
The bearing consists of a set of caged rollers which ride on two, super-smooth and hardened race washers. The hardening is very thin. Once the bearing wears through the hard surface, the underlying race washer material erodes rapidly.
I suggest you join the LoopFrame forum on Yahoo Groups and ask for further advice there.
Bad bearings look like this:

Only two race washers are used but this pic has images of three samples.
Patrick Hayes
Fremont CA