The images above, help you understand why you would use our 90 degree gas tank fitting, on a 2012 - 2016 model bike. You can see the stock set up on the right, and easily understand how susceptible the fuel line would be. Sticking down in this fashion, leaves the line out there, for any tree branch to catch it and rip it off. Or even just puncture it. With 50 psi of fuel pressure in the line, any pin hole will quickly drain your tank and leave you stranded.
Our 90 degree tank fitting, shown on the left, is the lowest profile 90 on the market, and tucks the fuel line inside, in a way where it couldn't be any safer from damage.
Above is our #1 90 degree fuel fitting, for all tanks. You'd use this one for the 2012-2019 EXCF / XCFW / FE / FE-S bikes. You get 2 inside spigots, each of different length, to fit either the stock tank, or you can use the shorter one, to fit any aftermarket tank.
I understand why you wouldn't think you need this on your 2017, as it already has a 90-Degree, but there are 2 good reasons:
One, even if you never get an oversize tank, the stock one is more restrictive than this one and causes the bike to start leaning out, as witnessed on the Air/Fuel ratio meter, when pinned in 4th gear on the 350 and 450, breaking the law around the hard core streets of Paradise Valley, Arizona.
And two, it will fit your oversize tank if you ever get one.