What oversized tank allows the original seat position or as close as possible. I need a larger tank, but the ones I have see so far make the seat look like a XR400. We commonly do 80+ mile rides, and carrying a gallon of gas on my back sucks for the first 40. I just sold a XR400, and hated the seat style compared to my WR. It sounds like most like the ACERBIS, but I don't want another ski jump keeping me from sliding forward.