My first tank low fuel light come on. Filled up with the auxiliary tank. A day later fill both tanks got 29.5 MPG. I can live with that.
Your are gonna get better mpg in mountain riding than us flat landers, that's just the way it works. Are you riding two up?
What brand m/c, GW, HD, other?
Mine 90gw---tall shield--me very large
Yes, I think near that 70 mph mark, the rpm is approaching 3K which starts sucking fuel. Believe the 1500 was a 4 cylinder w/carb? So I'd guess the 4 cylinder would be turning up higher than 3K at 70, very thirsty.