Just removed from bike; this happened after a belt slip at 70mph. The valve has melted into the piston. The other barrel/piston appears to be undamaged. Managed to get the piston and barrel removed. I don't think this damage will 'buff out' somehow. Next step is probably to split the crankcase. Looking at a rebuild, keen to attempt but not sure this is feasible unless you're a professional engine builder.
:Wideyed: Yikes, that's nasty. Will need a rebuild but unless you can do it all yourself and/or you are after doing something special (tuning etc.) then it may work out cheaper just to buy an 'ebay' engine.
It's not melted into the piston, the valve head snapped off as it was hit by the piston, which then had no where to go and was hammered into the piston crown! Nasty, but a Ducati engine is a simple thing to strip.
It needs a full strip, any alloy or aluminium sulphate from a blown piston is like grinding paste to a bottom end even it if appears to be good.
Pistons are the relatively replaceable bit. Show us what the inside of the cylinder head looks like. Thats the bit that will cost the most to sort out.
I think bolts must have loosened, but what's done is done. Funny how it was the front belt which slackened but the rear pissed and broke.
Hope you can get it sorted......... When you re-build, renew the special washers under the tensioner bolt heads...........they can lose their grip after several belt adjustment services....
