The stock fuel cap on my '92 Seca II (the faired, red one) had a chip taken out of the seal and it would continuously vent and slurp as I rode. It was driving me nuts.
Remembering how much I loved the R6 fuel cap that I used on the '97, I decided to run some EBay searches and see what I could find. I bought THIS R6 fuel cap for $8 plus shipping. It was listed as being from a 2006-2007 model. The key was gone and some PO jambed a screwdriver into it and got it to open.
The cap came tonight and other than the damaged lock tumbler, its in good shape.
I began by removing my stock fuel cap and disassembling it to remove the tumbler. To do this, I removed the two screws on the underside of the cap and lifted the latch mechanism upward. I then lifted off the seal and springs, compressed the tumbler keeper and pushed the tumbler out.
I then did the same thing with the R6 cap. To my delight, the lock cylinders are the same between the R6 and the Seca II. SCORE.
Now, if your Seca II still has the original fuel cap and you can use one key for both, great. Install your original lock cylinder into the R6 fuel cap and reassemble. Problem solved.
In my case, the original cap was long gone and I had two separate keys. I think "this sucks" every time I have to open the fuel cap as I have to dig around for the other key.
So tonight, I pulled out the wafers from the tumbler and, using a slew of spare wafers that I had from a spare ignition switch, found a combination that worked.
I was able to get close by swapping wafers and then I sanded the wafers to get a good fit.
When said and done, I had a rekeyed R6 gas cap that worked with my ignition key. Hell yeah!
If you're considering doing this, buy an R6 cap without a key. Look at the pictures and make sure the seal and finish look good. Not having a key will save you a small fortune and you're going to rekey the thing anyway.