The valve timing is perfect but you have bent all the valves ?
Can anyone explain that to me?
Like Flaps ,I rebuilt my M96 and am having difficulty understanding this unless....
The torque on the sprocket at start-up caused it to slip on the shaft. Mine is the Hi-vo chain system. That would explain the bent valves.
When you tried to start several more times, the sprocket continued to slip/rotate until it (magically) returned to the original, correct position.
Speculation pointless except for curiosity.
When you rebuild ,pin the shaft+sprocket.I posted a link to John Edwards Costa Mesa R&D doing this job some time ago.
https://www.youtube.com/watch?v=XP6GwqLvD7Q