I just recently purchased a keeway venus 50cc scooter. I am trying to diagnose what the problem with it is. It starts up fine but only if I pull the throttle all the way open. On a cold engine it revs and i get some response from the throttle if i lessen the gas a little, but after running awhile, if i ease up on the throttle, it will idle and the only way to get a response is to bounce up and down on the scooter. It then seems to get gas and run like it should. Also the only way to keep it running without stalling on idle is to keep the throttle wide open and apply the brakes at stops with the throttle still wide open (which i am sure is not very good for the scooter) B4 i bought the scooter, the previous owner told me it had been sitting around for several months unstarted. From what I have been able to gather about the problem, it could be a dirty carburetor from sludge leftover form the gas evaporating. My guess is the needle is sticking and that's why when I bounce it will go. ANy body have any opionions on what it could be and also how to fix it without having to take it to a repair shop? Any help would be appreciated! If you have any further questions i'll be glad to give any more information.
Thanks!
P.S. I dont believe that there is an idle adjustment on the bike and i do know it has an automatic choke on it.