There should be a breather to stop a vacuum forming shouldn't there? No problem with mine in 850 miles.
Jerry
I had this issue with my triumph tiger 800xc. Drove me nuts that my friends would pull over for me to get fuel while on their v strom and versys. And then I couldn't get it open. Embarrasing!:|hope it works out for you!the fuel tank lid is difficult to open..... the inner pressure seals it to the tank and I have to strongly pull out using the lock's cover till air comes in (pppssssssss)
someone else has same issue?