Re: Need some help and advice......
Your carb is a diaphram type that 'sucks'. The two lines are for fuel and vent. The same system is used in the new Titan, (HS) 35cc motors. The tank cap is non vented. I would probably go with Bike Guy Joe's advice; run a fuel line down from the upper tank with a petcock between it and the lower. Use the upper as your reserve but remember you'll need to vent the upper tank so fuel will flow when you open the petcock. Retain the non vented cap on your lower tank to prevent overfilling and leakage.
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