No, they are not changeable. Both have terrible shapes and performance overall though, even adding more weight would do very little to help. Draciel S, and to a lesser extent Draciel MBD are the only worthwhile draciel beyblades.
Also, you can't legally put three sets in F, it's an error on the wiki, (there are a lot of those). I wrote a better draft in the Draciel F thread in the beywiki subforum, though it needs a small tweak in terms of formatting, the information in it should be 100% correct. The most you can do is two sets and that's only with certain weight disks (to prevent them flying out), and without it's own SG, as that blocks them, which requires the use of one of a small selection of tips, all of which are aggressive and have poor stamina. The only way to put three in is to use specifically sized metal balls that can sit in the four holes that hang down from the base, and there are no balls of that size in any release.
Also, you can't legally put three sets in F, it's an error on the wiki, (there are a lot of those). I wrote a better draft in the Draciel F thread in the beywiki subforum, though it needs a small tweak in terms of formatting, the information in it should be 100% correct. The most you can do is two sets and that's only with certain weight disks (to prevent them flying out), and without it's own SG, as that blocks them, which requires the use of one of a small selection of tips, all of which are aggressive and have poor stamina. The only way to put three in is to use specifically sized metal balls that can sit in the four holes that hang down from the base, and there are no balls of that size in any release.