Time to pull the curtain back on a project I have been working on for a while. I love my F800 and have since I bought it. My only real complaint is the fuel range of the stock bike. I tried a few extra fuel options. All had their pluses and minuses. Ultimately, I wasn't totally happy with the options available. I started plotting and planning a couple years ago with these needs in mind: -hold roughly 2 gallons -not interfere with a top box or duffle bag -work with hard panniers and racks -not require a fuel pump for transfer I'm sure some of you figured out what was going on with these threads: What panniers are you running thread Auxiliary fuel tank thread Here's what I came up with. MCMXCIVRS was kind enough to let me install the tank on his BMW pannier equipped F800 to test the fit.