Moin, have a question about the vacuum. Have a Gilera Runner sp50 bj 99 If I want to start it it takes forever until it starts. When it’s on it runs completely and without problems. The carburettor is completely clean. If I suck at the vacuum hose no gasoline comes out. If the vacuum hose hangs on the carburettor and I still have the petrol hose off and e.g. per e starter tries to start petrol comes out of the hose. Is the tap broken or not?