Just wondering, if a famicom disk has 2 games on it, does that mean its a bootleg or was there ever a legit way to put a second game on a regular yellow disk? (I know the blue ones were from the vending machines and rewritable)
What two games are on the disk? I think you could put a yellow disk in a kiosk if it had a blank side B and still get it to copy a game. Does the disk have a retail label because I thought all legit yellow disks had a label on them.
It does not mean it is a bootleg. The Disk Writer service certainly could be used to write a new game on the unused disk side. It's probably reasonably common to find disks like this. The color of the disk doesn't matter. They are all rewritable. If you had a single sided game there would be no reason not to go to a store and pay to have them use their disk writer to put a game on the unused side.
http://www.nesworld.com/article.php?system=nes&data=fds-gameslist Working on it... Also an original disk with two different games on it most likely means it was used in a Disk Writer Kiosk and someone bough a single sided game fro the empty side of the disk.
As everyone has already said, most FDS games have a blank side, with the idea being you take it to a kiosk and buy a second game and have it written to the blank side. Hell, they were even designed for you to be able to erase the game it originally had and replace it with a new one. Which results in a lot of games not matching what the sticker says it has.
Having an mgd1 setup, I myself have put games on the other side of disks, but only for personal use. On a side note back about a year ago there was I guy I suspected of writing disk since he had 2 copys of all night nippon without labels. I feel like that one of the biggest problems with the famicom disk system is its easy as hell to fake a game if one wanted to and there is a few fellow collectors out there actively faking them. For that very reason I wouldn't collect for the fds if double game disks are a concern.
Well, that's the price you say for having a rewritable media for gaming. Nintendo's aims are nice (Cheaper media for rewritable games, everybody sames money!) but piracy killed it much.