It happens to all my throws from yoyo factory but not a single other throw. I use it and it makes it’s normal sound from spinning. But after a while, it gets really loud and actually annoying. The noise changes. I switch to a different throw for a while and then go back to the yyf. It’s back to normal but after about 10-15 throws, the loud noise comes back. It’s so annoying, it makes me want to not touch that throw anymore. Any ideas on how I can fix this?? 
Try giving the bearing a good soak in some mineral turpentine, apply one small drop of lube, spin the bearing on a pencil a few times to spread the lube, blow on the bearing to remove the excess lube.
Yuki
Any advice on some good lube to get? I haven’t had a chance to buy any…ever.
YYF or YYJ thin lube or One Drop V4M. All seems to do the trick.
Yuki
YoYoFactory tends to ship their bearings lubed just the right amount so it’s perfect when you get it, but the lube wears off after while and requires more. Don’t clean it, just add a drop of thin YYF or YYJ lube and break it in again. Repeat when it starts to get loud again.
V4M lube is definitely the best in my opinion, and a lot of others agree