Front vs rear iso effects on levels of vibration

Hi,
In the past I have read somewhere that front and rear isos, respectively, control vibrations through certain bands of engine RPM. I can't remember which set, front or rear, supposedly effected what RPM range, could anyone out there offer any enlightenment. Presently my bike is pleasently smooth from 3000 up, but, below 3000 it will literally shake my eyeballs.
I ride my bike like the proverbial old lady, so, I am tempted to just pull all the shims and leave them loose as a goose in the interest of comfort. Have any of you or anyone you know ever tried anything like that, and what was the result?

GB

Consider yourself lucky, my commando does not smooth out until about 3500 rpm.
Don't know if you have adjustable isos or have to do the time consuming shim thing?

Your bike sounds pretty normal, shaking up to 3000.

The risk of too loose isos is possible loss of control, particularily the rear iso being so loose as to allow the swingarm
to move too much side to side, dangerous.

What year commando, and are the isos readily adjustable, or shimmed?

Lots of recent comments on posts relating to setting up the isos for correct clearance, vibration, control.

Hi again,
My bike is a 74 (shim adjusted iso), the first winter I had the bike I went through the isos and replaced all the boots, rubbers, and washers. I thought I was being smart by setting it up somewhat tight, that was a mistake, at road speeds above 50 mph it was uncomfortable. It wasn't untill I loosened up the back iso that things smoothed up above 3000 RPM. In my question, I was hoping someone could tell me whether or not loosening the front iso would have the same effect on vibration below 3000RPM. Seeing that the front iso is easily accessed maybe I'll just loosen it up as an experiment.

GB

I have installed new front ISO and adjusted to spec and never touched the rear. Vibration disappears at about 2700 RPMs and doesn't reappear, and handling is excellent - so it can be done!

Well, this is from the Norton Tech Manual.

Vibration: up to 3000rpm rear engine mount tight, front mount ok

from 3000-5000 rpm: front mount right

from 0-5000 rpm: both mounts too right