I've looked into this a little further and thought some members may find the information useful.

I dug out a road test of the 1996 CBR1000F from Bike Magazine (UK) from October 1996.

Under the specs it has a wet weight of the machine (full tank of fuel and oil) of 597 lbs.

It also gives the weight ratio (the proportionate weight over the front and rear wheels). This is 48% front / 52% rear.

So, this means 310 lbs over the rear wheel and 286 lbs over the front wheel.

I've taken a look at the info on the sidewall of my tyres (I use the wider 180/55 at the rear and standard 120/70 at the front). The max weight capacity of the rear is 805 lbs at 42 PSI, while the front is 520 lbs at 42 PSI (I run on 36 PSI at the front).

The way I understand this is that it would be incredibly difficult to go beyond these weight limits for the tyres and so long as one is sensible when loading luggage onto the bike (i.e, pack as lightly as possible) there should be no problem. This of course assumes that riding stlye is adapted accordingly.

Anyway, thought these figures may be of use to other riders.