Originally Posted by rube
I don't think there are any aftermarket tank options which significantly increase the tank size. Am I wrong?
I think Clark makes a plastic aftermarket tank for the KLR250; not a great increase in volume over OEM, IIRC.
But . . . you already have a Cyclerack; you can get pannier hangers from Cyclerack, with sheet metal plate drilled for a Kolpin auxiliary fuel container bracket, and rig up something like this (you don't have to have the panniers and top case):
KLR650 shown, but . . . accessories fit KLR250 Cyclerack also (I have both).
I use 1.25 gallon Pioneer container; the larger Kolpin and maybe other containers (e.g., Rotopacks (?)) will fit the bracket also; don't know about the clearance with the larger vessels, might have to mount them outboard. If you mount auxilary fuel containers both left and right side, the right one MUST go outboard, IMHO, to clear the exhaust heat sufficiently.
P.S. No pumper carb expert, I, but . . . I imagine you could improve your fuel mileage by 1) Re-jetting your carb, and 2) Avoiding opening and closing the throttle excessively; as you know, each time you turn the throttle you squirt raw gasoline into your venturi! Again, conjecture and speculation, ideas offered in hope they might be helpful in improving your fuel economy.