I have to spray ether into the air intake to get the bike running and once I get the bike running I have to keep the throttle over half way open to keep the bike running. The bike doesn’t want to idle or start without the shot of ether. I rebuilt the carbs on the bike and replaced the whole fuel system “due to the last person to own it left fuel in the lines for over a year”. I have ran out of ideas on what could be causing this issue. Any help would be greatly appreciated.
Your low range jetting is blocked by the sounds of it, going on what you said about the old fuel (which goes likle varnish) when left. Ultrasonic cleaning in order, a quick thing to check is there an air leak around the manifold.