I have just found out a new mod that you may or may not have tried. I tried to put silicone at the rims of my FAST 201 to try to add extra rim weight. Silicone is quite heavy, so it will generally inprove the spin of the yoyo.
http://i627.photobucket.com/albums/tt358/mrcinimod/IMG_1547.jpg
What do you think? Would it work?
It will cause serious vibe problems. You need to be extremely precise in getting the exact amount even all the way around the yoyo. Also you will need the other half to be exactly the same or you will get the dreaded gyro turn.
I’ve tried this before actually.
it took me several tries before it was a little viby. If you really want to make it a player, Silicone recess it. It is hard because of the response holes bu t it makes it an amazing player. You can also switch the bearing out with another bearing and some fitting Duncan spacers to make the gap larger.