Just picked a slightly used 2015 1290 SDR with only 1100 miles from a dealer here in seattle.After one ride
of 45 minutes noticed a burning smell and low and behold there is an oil leak coming from what seems to be the
head gasket on back of the rear cylinder.Oil drops down to the flat part of the case and will pool up there a little
and inevitably will drop to the exhaust hence the burning smell and slight smoke.Not an excessive leak but definitely
something that needs to be addressed.The bike is under factory warranty for another 6 months.I"m the second owner and
will contact the dealer tomorrow.Hopefully no issues regarding it being covered.Any one else have this issue?

Not heard of that one yet!
The castings of the clutch cover and flywheel cover are extremely light and some have pinholes in them due to the metal seemingly being aerated to make it lighter, that's where most leaked.
On the other hand the gaskets everywhere are exceptionally good quality so they hardly ever leak.

Get the dealer to tilt over the bike to the left too and inspect - replace the oil filter as there have been issues with that and it raises the oil pressure which causes leaks.
10 min job and if leaned over hardly any oil comes out, piece of mind!

See here:

Tip for the clutch cover: A piece of 2x4" timber under each wheel and the bike on it's side stand was far enough over to minimise oil loss last time I had the cover off.