Engine rebuild...

[max]

Thanks for the nice pictures, as you can tell you have our attention.
As a sympathetic audience we could do with some more information;
does the vibration happen when the engine is stationary and at what revs is it worse?
Is there a noticeable lack of drive and when the engine warms up are all four pipes getting hot at the same pace?

It happened from one second to the other, i wonder if the cylinders are contributing equally or if an injector is not working as it should

Found a picture of another cb1100 cylinder with cleaned pistons in front, notice the scraping on all 4 pistons/cyl's.



(click twice for larger image)
Not sure why pistons all score in the same place and I guess your cylinders were scored deeper?
And looking at where the scoring takes place ( well below the rings ) it makes me wonder if it's not something in the oil that gets splashed up to the cylinder walls that causes this?
I mean how does the carbon get past the rings unnoticed and settles below the rings to scrape away at both parts?
I'm sure we all feel the unbelievable misfortune that happened to you and wish for a fair outcome from Honda.