Hey guys, I was wandering if any of y'all have used the 18/38 sprocket combo and if so how much low end difference have you noticed and has it helped on mpg over 18/40 combo? I know I want to change my sprockets but trying to decide which way to go. The area I live isn't super hilly but there are some decent inclines though. I ride mostly one up and even on rural roads I keep trying to find another gear. My bike is a 1998 800b. Thanks in advance for your replies and info.