Won't start, with loud bang's

[b1k3rdude]

I guess i have to take out the entire engine now

Not necessarily, check with your local engineering shop or a good mechanic. If there is enough clearance around the top of the engine and the frame, that will give them a good chance of them getting it out for you. Worst case yes the engine will need to come out, but on the FZS1000 that easy due to one of the frame rails being removable.

In the photo I can see lots of dirt on the camshaft and its lobes (from pressumably when took the cover off), you really don't want this going into the engine.