My girlfriend has a 2006 vstar 650 classic. it sat for 2 years. i put new gas and ran carb and fuel system cleaner thru it. it idles fine but as soon as you give it just a little gas it stalls out. no matter how slow you turn the throttle it stalls out, but as i said it will idle just fine. can the carbs be out of sync? am i getting fuel to the carbs? it doesn't smell like it is flooding out, i get no gas smell at all. what do you think it could be.

SOURCE: Vstar 650 classic. only will idle.

hello and welcome
this is a very very commom problem after the cycle has gone over a storage period of anything over a month or so. what has happened is the deteriorated fuel has plugged the idle jet, and possibley other jetting. this is verified by pulling out the choke allows it to run. because this makes of for the loss of fuel the jets are not produceing. so to fix this you will need to remove the carbs and take out the jets and clean them thoroughly with a carb cleaner and possibly a very small gauge wire to break up builup. especially in the pilot jet. unfortunately fuel added carb cleaners dont seem to work for this kind of problem and to fix right they should be disassembled and cleaned thoroughly. thank you.

SOURCE: twin mikuni carb adjustment

You can make a duel carb sync tool for about $2

Here is a link to a walkthrough for making the sync tool

CARB SYNC TOOL

Here is a link to a walkthrough for doing the carb sync

CARB SYNCHRONIZATION

Don't worry about the air-fuel mixture. It doesn't need to get adjusted.