I reinstalled both carbs today, along with replacing the fuel lines and fuel filter. There's been discussions about how fuel filters restrict fuel flow, and possibly cause problems at highway speeds. I was going to drain the fuel tank and remove the petcock for cleaning, so I decided to check the flow rates for no fuel filter, and fuel filter installed. The results that I got were : no fuel filter petcock ON: 7.8 gallons per hour, no fuel filter petcock on Reserve: 13.6 gallons per hour, fuel filter petcock in ON: 7.4 gallons per hour, fuel filter petcock on Reserve : 12 gallons per hour. I figure at legal highway speeds here in Arizona (75 mph) that I'm probably at 1.8-2 gallons per hour fuel consumption. So it doesn't look like the fuel filter is going to cause any problems for me at least. I am using a common clear plastic filter with a sintered filtering element. I also tested an old filter with 3 years on it, and the results were within 5% of a new filter. Yeah , I was really bored today, but somebody has to do the testing to blow the generally accepted myths away ! Also, after draining the tank with the petcock on reserve, I got 60 ounces of fuel out of the tank with the petcock removed, so there is a little under a half gallon US of 'unuseable' fuel left in the tank when reserve is depleted.
