Thanks to all those who advised me on how to refill the antifreeze, etc. This comes under FYI.
I live a few miles from the Natchez Trace Parkway, and there is a short ride I take down to Rocky Springs (about 100 miles roundtrip). Call it 2-wheel meditation or therapy. Works every time. At any rate, before my recent changes to the bike I always got 47.8 to 48.1 mpg. I know it's a high number but the speed limit on the Trace is 50 mph and that's what I ride at (actually cruise set between 50 and 55 to allow for error). With Yamaha oil and filter, stock paper air filters, and stock exhausts, I got my routine figure of 47.8 mpg last week.
Since changing to Mobil 1 motorcycle synthetic and Pure One filter, K&N air filters, and Bub slip-on exhausts, I have now gotten 51.2 mpg on one trip and 51.7 mpg today. This is a pretty controlled experiment as I always fill immediately before getting on the Trace and refill at the same place/same pump immediately when exiting. Same fuel (Exxon regular), same pump, same trip and speed.
So . . . those of you who are worried (as I was) that intake/exhaust modifications would adversely affect gas mileage should worry no longer. Did I mention that the Tour Deluxe feels and sounds like a new bike? Incredible difference!
Thanks again to all who helped with advice on exhausts, refilling the radiator, etc.