Motorcycle Repair: Honda CB500 T caburettor spitting, honda cb500, carburettors

Question
Hi
Valve clearence okay , timing (with oscillator) and points adjusted 0,3 - 0,4 . (points in good condition)
Especially the right hand carb goes on spitting .... tried to turn the mixture screw under the vacum screw  .... no better result
Isnt it 1,5 turn out from zero ?
What is the problem here ? Plugs are all new - NGK BP 8 s

kr
Cn  

Answer
More likely old fuel in the carbs, take the carburettors off and give them a good thorough clean.  1.5 turns out from closed is usually a good start but this varies between bikes; your manual should have the correct setting.  
If you feel the carbs are clean already, then you could check the HT leads and the coils if it is an ignition issue.  Good luck,  Jan