here's my civic pulling a bike from indiana to colorado, a trip of 2k roundtrip. last year I did the same thing but I left my saddlebags and windshield on the bike. I ended up getting 30mpg which wasn't to bad, although my normal mpg without the trailer is 44. this year I took off the bags and shield and streamlined the bike a bit.(good thing it didn't rain) my mpg this time jumped to 38mpg. just a little bit of effort made a big difference. here's some pics to show what I did.