For all of you who helped me about this one ..

GUESS WHAT!

The piston was Slack in the cylinder ! .. I thought it was within specs, but the guy of the dealer told me that I need to go
to .5 Over-Bore and new Piston!! ..
The guy told me that In principle we should not be able to insert the piston by the skirt from the top of the cylinder.. and
the piston was so slack in the cylinder that it was easily inserted in the cylinder ..

The guy also told me that I was probably at 50 lbs of compression ... And I found the quad Strong.. .So I don't really know
what I will have after the rebuild, but if it was at 50 lbs, then I will have a Real TANK ! ...
Anyways.. He told me that the piston was surely rattling ( is that the term, sorry I'm a french guy ), in the cylinder . ..

Sooooooo ... I conclude by saying that it was Surely the source of all the noise of my engine and also the source of other problems!