I have very few of these, just the one or two for each time I have tried to mend my bike which I have only had 18months.
so far there was when the Carbs were leaking, I managed to take them off and service but then there was a leak which seemed different. First one had been because the float was keeping it open. New one was because of a crack in the float bowl. That crack must have been me over tightening the drain screw. Not the end of the world that one, I took a bike that would not start and got it to the point I could ride it to the garage. Shame I did not take time when putting the b