after the winter sleep I took apart the bike , cleaned somewhat, the vacuum nipple lost, not able to find.
it has been lost on a 2 m2 area, was only two movement: to set aside the fuel tank and an other to take back, without any necessary movements. Done many times never thought it could go away it is held on its place with such big a force.
and still shit happens
it is so overwehlmingly painful I was not able to bear the sighting and thinking of the bike for 3 month.
so if anyone has an idea how to replace the tiny vacuum nipple on the petcock ?
(aside the obvius to buy a whole petcock)