Join Date: Jul 2017
Location: Snohomish County, Washington State
Year/Make/Model: 2007 Kawasaki Vulcan 900 Classic LT
Color: Black & Silver
Hmmmm ..... if you have been doing your oil changes with good quality motorcycle oil on time, and not just abusing the bike to death, I rather seriously doubt "all the parts" of the transmission would "normally" wear out in 54000 km/33,500 miles. And I even more seriously doubt that the "quality of the material inside" is "not that good any more." Japanese manufacturers in general are rather famous for superb metallurgy and machining and for being fanatics about quality control. They have, after all, been making astonishing things out of steel since the days of the samurai. These bikes regularly go 50,000, even 100,000 miles (80,000 to 160,000 km) with few problems, and certainly without major transmission failures. Not that failure is impossible, but I'd say it's quite unlikely given good maintenance.
On the other hand, I have no explanation for the different sound you are hearing. I'm not sure what the picture is supposed to prove -- it's small, but it looks like a view of a gear. So what? Does he have any solid reason for thinking you need a transmission rebuild other than, "It made a funny sound and I have an opinion?" To me, it seems like a doctor saying, "Well, you look a little pale, and I don't like that look in your eye. We're going to do major heart surgery on you."
As to your warranty situation, I'm afraid I'm no expert on Romanian law. In the US, your aftermarket parts would not void your warranty for the transmission, unless they could prove those parts caused the transmission failure, which they can't prove. In Romania, things may be different. If it's covered, and he says it needs rebuilt, I say let them have at it so long as the work is warrantied. If it isn't covered, I'd probably just drive it till it broke, then rebuild it.
"Don't force it. Get a bigger hammer."
- William Shakespeare