I have a tank from a 1980 xj650 Maxim that is JUNK. BUT--- the cap is a bit different than the usual ones, so I figured I'd save it and someday get it removed. I never had a key for it. As things go, I've learned how to pick cap locks so I don't have to ruin them by drilling. However... no amount of picking would get this open. So, since the tank was junk anyway, I cut it open. Now we can see inside an old tank. Of course, me being me, decided to see if I could rescue the cap anyway. Once the underside was accessible, I could see why it wouldn't pick open. The cap The keyhole cover is nice. Can I save it? Yes!! As soon as I got the cap loosened a teeny bit, the springs snapped the "gate" closed. I removed the assembly and picked yet again....with a bright light, too. This time a big screwdriver gave just a little added help and the cyl turned. But the cap still wouldn't release. Inside the tank Well! No wonder it would not open!! The dogs are stuck. I bet the screws will strip right out. No! They didn't You just gotta LUV the JIS screwdrivers from Len !! But-- the dogs weren't stuck to the tank. Nope.... the are rusted to the plate they should slide on. Did I forget to tell you that when I finally got the cylinder to turn, it turned all the way around? Hmmmm--- maybe it was because the bottom of the cylinder that moves the dogs had rotted off.....Eeewwww, that's messy. But, the springs came out, the check-ball came out, etc... The dogs were let loose... the o-ring came off--it just might be do-able! Yup, definitely broken But wait-- didn't I say I don't have a key?!?! Yup.... this is a key that happens to slide in. That way I won't lose any springs or wafers. The key traps them until I can wrap tape around the core. I don't want to lose any springs.... they're about the size of a squished mosquito After some cleaning, (ok, A LOT of cleaning, it's ready for a rebuild kit from Len. Yep, he carries all these parts, too, and instruction on how to rebuild gas caps have already previously been posted. Oh yeah.... you probably wonder how the outside looks. It's not perfect, but it will live for another 38 years now..... for now, it goes in a baggies until I'm ready to re-assemble after de-rusting some of the parts, and getting other new parts.