to only get 100 miles per tank .... you must be riding in first gear at redline, or soft deep sand. I think something is not right with your bike, but the tires should make no differenceIt's a 120/70. I'm currently trying to figure out why my gas mileage is so bad. I do drive very aggressively, however I'm getting 29MPG and only 100 miles out of a full tank.
After I had my ECU flashed it ran rich, really rich. Smelled horrible to the point where it was almost un bearable when running. Thats when the MPG kept dropping and dropping and finally stayed at about 29MPG. I have since had it dynotuned where they tuned the fuel down a bit however its only gone up 1mpg. I changed the oil to find that there was a bit of gas in it.. Should be normal from it running so rich. Soon after changing the oil I filled the gas tank and decided I would ride very conservatively to see what kind of MPG "I could get" if I don't ride so aggressively. I'm currently at 2 bars on my fuel guage with 90 miles on this tank of gas. I predict that I will get to about 130-140miles until the tank is practically empty. I'm concerned that I've got a bad piston ring leaking fuel down to the oil pan OR bad valve seals. With riding the bike hard on a tune that was way too rich for about 1,000 miles I wonder if that could have damaged one of the internals.to only get 100 miles per tank .... you must be riding in first gear at redline, or soft deep sand. I think something is not right with your bike, but the tires should make no difference