rl, You are AT LEAST 15mpg short. I don't think the wickers among us with highly moded bikes get that low. I would check first and very carefully for leaks. Or a brother-in-law with a siphon hose.  

They are city miles ,my idle isn't really high, I don't see anything on the floor under the bike, I do get into it a bit when I ride ,nothing unusual. It seems last year ,it got better mileage. I put seafoam in it once this year. Thanks for your input.

He doesn't know his reason for his low gas mileage.

He has to find out why he gets the same mileage I do.

Start with simple stuff -- clean your air filter (or replace it)  Plugged up air filters can cause very rich run conditions.

Clean or replace your plug with a nice new one so you can see if the rich running conditions abate after replacing the air filter.

IDK how fast youre going b4 ya change gears, but this bike has Torque,,change gears with the engine loafing,, High gear at 40 MPH is okay..
Your best MPG is found at the lowest speed you can get in high gear & not lug it.

I've never checked my Savage's gas mileage.  I use it primarily for short commute to work and running quick errands around town.  All I know is that it's a HELLUVA lot more than I get with my Suburban or our Chrysler 300!!  
And ALOT more fun to ride! not to mention easier on the wallet than filling the 40 gal tank in the Suburban)

I ride the snot outta mine & I have the Stage 1 cam & a Supertrapp with 14 disks & I get 49 MPG.

I've got the same problem. Plug is black, pipe is black.  86 model, stock carburetor, stock muffler.  New air filter and a Raptor petcock.  Needle has the stock white spacer.   Cleaned the carburetor (soaked) at least three times and blew it out with compressed air and I'm still only getting max 37 miles per gallon.  It has about 8,800 miles on it.

I'm a conservative driver and travel mostly open back roads with few hills (not many of them here in Florida.) at between 55 and 60 mph.  Very seldom do I romp on the throtle.  The bike seems to have more than enough power to pull my 260 pounds down the road.  It only requires a little over 1/4 throttle to maintain 55 - 60 mph, flat and level and no wind.

I also replaced the main and pilot jet thinking PO might have messed with them.  155 main and 47.5 pilot.  I wnted to replace the needle jet and needle but they're out of production.  New dle screw and O ring and it's set at 2 and a half truns out.

I plugged the choke (starter enrichment valve) opening thinking it may be leaking extra gas into the venturi.  

Also forced the deceleration valve (air shut off valve) open so it can't close.  That does cause a little exhaust backfiring when decelerating but not bad.  I get the standard pop when shutting it off.

I've got the float set at the very lower limit also.  The 86 doesn't have the drain valve so you can't check the gas level with a tube like Verslagen suggested.  Even replaced the float, float needle and seat.

In all from what I've done the mileage did increase from about 34 to about 37 but that's no where near what I've seen reported here.

Bike starts and idles perfectly even without the choke.  If I get on it at 55 it'll be going past 75 in a heartbeat. Then I chicken out.

I do have a little studdering (miss) at low speed like when driving through town but that has actually improved since I made the changes I mentioned.  I think that's tied in somehow to the poor mileage problem. Too rich.