So I just put a new 3.1gal. IMS tank on my 450 to get ready for an off-road race this weekend. The race is 100 miles, 2 50 mile loops. In previous years average speed was around 45mph. The terrain is described as sand washes, jeep trails, and two-track roads. The loops have never been 50 miles in the past though. I got to looking at the forum for the series that is hosting the race and everybody is concerned about not being able to make a full loop on a single tank of fuel, even with a desert tank on their bike(none of the posts were make/model specific)... Does that sound right? I would have thought I could make 50 miles pretty easy with a 3 gallon tank? Just wondering if anybody has ever calculated mileage on a YZ 450? Guess I'll find out soon enough huh?