1098R, oil thru pot and into exhaust, gumph!
 

Hi, the bike sounds OK but obviously the heads are gonna have to be whipped off for a butchers.
I've heard from a reliable source that the pots can glaze with hard use and cause this problem... Any ideas peeps? Cheers.

or possibly valve guide seals, not sealing especially the exhaust one

Cheers skidlids, yeah I've heard it could be that too which makes sense. We'll be whipping the heads off shortly for a look see...

Turned out to be a cracked piston... And the crack had propogated right through and round the gudgeon pin bosses.... Yikes! Nearly lunched the complete engine.

Unlucky to have such a fault, but very lucky not to do some serious damage