XSLeo
XS400 Junkie
On my 81 XS650, it had the same problem. The b umps that engage the slide were worn away.
On the advice of another member on the XS650.com site I took the slide part out of the cap, found a strip of steel the same width and a bit longer, long enough so the strip of steel stuck out from under the cap about 3/4 inch or more.
I cut a cut one end of this strip to match the slide part of the cap. Grind off any of the nub on the key part so it won't interfere with the new slide.
Now with this strip mounted in place of the slide and sticking out from under the cap A bent up the strip about a 1/4 to 3/8 inch from the cap. Enough room so when you push on the upturned end of the strip it could unlatch the cap.
I then cut and ground the upturned end to a rounded shape.
Now you don't even need a key. Just push down on the cap, press on the new release and the cap pops open.
Leo
On the advice of another member on the XS650.com site I took the slide part out of the cap, found a strip of steel the same width and a bit longer, long enough so the strip of steel stuck out from under the cap about 3/4 inch or more.
I cut a cut one end of this strip to match the slide part of the cap. Grind off any of the nub on the key part so it won't interfere with the new slide.
Now with this strip mounted in place of the slide and sticking out from under the cap A bent up the strip about a 1/4 to 3/8 inch from the cap. Enough room so when you push on the upturned end of the strip it could unlatch the cap.
I then cut and ground the upturned end to a rounded shape.
Now you don't even need a key. Just push down on the cap, press on the new release and the cap pops open.
Leo