hi guys i have recently tyaken my ke20 to work to get the carby looked at. my mecahnic says that its not running rich enough at idle, even with the mixture screw turned all the way out. Aparently i need to drill out the idle jet, when i have looked at the work shop man, i think it might be the slow jet?? or is this just the air bleed for the idle circuit?

is it just the stock motor? And are you using say a 3k carby on a 4k, as you have a ke20?