I have a 1975 Honda CB 125S it is a great little bike and my 11yr old is chomping at the bit to ride it. it runs fine until it gets warm and then refuses to idle. I have adjusted the idle but think think it has a rich mixture. I have heard about the ethanol in gas on older motocycles, but hell were these meant to run on leaded fuel? Any how can anyone show me how to adjust the air fuel mixture right so I can get my kid to ride it with out having to mess with the throtle at a stop?