Since I got this bike I couldn't help but think the perches weren't at the same angle because the mirror arms weren't aligned - clutch side appears more upright.
I couldn't understand why this was though as both levers were level.
I have just changed the mirrors for some sleeker looking ones, ones that give less wind blast. These are the Aprilia rip off's (on fleabay) specials, and they are very nice looking, and seem to help.
However, whilst changing the mirrors it drew my attention to the angle issue again.. and I think I've found it.
The brake lever has very little wear and thus very little up & down play.
The clutch lever has more wear (as you'd expect) and more play, so has been adjusted to sit at the same level as the brake lever, to allow for the fact it's now hanging lower (it has more up & down play).
The nett result of this is that the mirror is now more upright on the LHS side.
I now plan to take the clutch lever out and see about making up a shim to take up the slack.
Should be a simple enough task and then I can re-adjust the perch so that the mirror arms are both at the same angle.
Should also help to balance the airflow around the screen too.
Just thought I'd mention it as I'm sure my bike is not the only one suffering from this.
I think having handguards highlights the lever sag more and encourages you to adjust the perch to take up this slack, thus moving the mirror out of alignment.