magilla,
I have the same issues as you. I have a 1997 XR 400 and a 2000 KDX 220. I can get exactly twice as many miles per gallon on my XR. The KDX will go 60-75 miles per tank in my experience. The Clarke Tank is 3 liters bigger then stock. The IMS is only 2 liters bigger (4 liters = 1 gallon). You can also get a tank the mounts in place of your headlight, the larger one holds 3 liters. So now you have 6 liters more with bothof these. I have also carried a 2 liter Coke bottle of gas in my fanny pack, so then you could have 8 liters more. If you could also find one of those handlebar mounted jugs that would get you another 2 liters and you would be up to 10 liters more, almost double the stock tanks capacity.
skipro3,
do you know where to buy those hadlebar mounted jugs. I have looked everywhere and can't find them!