Oil blow from top of transmission, under battery

I get an overflow of oil from what must be the transmission breather (?) some time after shutting down my K75C. It isn't a huge amount - soaked into a page of newspaper it comes to about the size of an adult's hand. The gearbox oil level is correct and it never happens while riding. This leads me to think it might be oozing out under pressure when the oil settles after stopping, but is hot. So perhaps a blocked breather? I will pull out the battery and tray sometime in the coming week for a better look, but has anyone experienced this themselves? (This 1987 bike has done 60,000 kilometres and until I got it back running about 300 kilometres ago had been standing unused for 15 years. The previous owner fell off it at low speed and lost confidence. The damage was minor - a holded crankcase cover and shattered fairing - but I have renewed all perishables and replaced the tank internals.) It runs well.

Dwanderer,
This is common when you overfill the oil and not stick to the "glass levels" recommended. Check this first before pulling it apart. If you fill by book stated amount it will be too high and there is a chance it will cover your rear tyre.
Kiss is the formula don't forget.
Ajays.

Dwanderer,
I had similar experience as you, Ajays advice is good but also check the breather tube from breather to the plenum at rear of and just behind the throttle bodies for small cracks, had to replace mine as previous owner had over tightened it and cut the tube at the plenum.
JohnC

Thankyou for the replies. The oil level barely reaches the bottom of the dipstick (C-spanner from toolbox), and the point about the breather tube connection is interesting. Mine just hangs down the back of the transmission casing, pointing to the ground....I will take the battery and shelf out this morning for a proper look.

Hi there, are you sure is transmission oil?
It seems to me that Ajays and John C replays are regarding engine oil
Best regards
JAP