[jorian]

I always bring supplementary fuel because I'm hard on the throttle, ride a two stroke and have run out of gas before. I usually have a couple of those red MSR bottles shown in the last pic and I have a 1 liter bottle strapped to the number plate up front. As soon as I have the space in my tank, I empty the bottles. Safer in the tank than in a bottle. Better balance too.

A friend has the XR400 and it seems to get about 40-50 miles per tank and maybe 5 miles on reserve. If your bike is stock you might get a bit less. Pipe, jetting and gearing make a diff. I don't think you'll get close to making the trip unless you bring an extra 8-9 liters (2.4 gallons) along with you. Oversize tanks typically give you about 50% more range which still isn't enough and they are expensive. Bring a tow rope - it saved my azz once.