This is another interesting 5 page long mysterious unsolved story of a defect scooter - which is usually rocksolid and reliable, if treated nicely. Although so many forum members tried to help and put so much effort into it, the owners just opted out all of a sudden. Hmmmm....
After reading carefully what Renee wrote and watching the videos of the cylinder head and the very wrong huge valve gap, my guess and conclusion is as followed:
The scooter´s last run with "beloved hubbie" on the highway was with either the wrong oil and/or not enough oil, or a defect oilpump, therefore it got too hot and seezed the valves/valvestems in open position. Therefore the huge valve stem gap. And therefore no compression. Looking at the open cylinderhead I also do not notice or see as much motoroil as I would expect or I saw in this aerea on my scooter´s engine.
Also possible now is a temporary piston seizure or piston damage via open valves. An endoscope camera system might help for further diagnosis.
Long story short: In my opinion this engine is dead.
And I am always a bit sceptic, reading about John and Jane Doe´s talking about themselves how experienced they are and what they have managed to do already "successfully" on their vehicles.
According to what dear hubbie has done to the scooter so far and how Renee tried to do the failure analyzis, I would recommend to both of them that they should better leave this kind of "service and repair" to real world professionals and mechanics.
It´s cheaper for them and maybe safer for all of us.
