Okay, I'll get on my gas (soap) cap box again. Mine was tight when I had the stock cap (and because it had a key sticking out of the middle of it, it was even harder to get a good grip on. I was always conscious that I might break off the key just trying to twist the cap off. I used grease, oil, gas, and everything but toe jam to try to lube it - and all would work for a fill or two and then it would get difficult to remove. I finally resorted to a nonlocking Yamaha cap which I can get ahold of if needed, and which I have never had problems with it being as tight. I have never tried bending the flanges but that should help. Tom