is it possible has anyone tried it grinding the nubs to spikes i might once i get a job and a less expensive yoyo to try it on like a lyn furry or kick side
Hmmm. That’s a cool idea. I don’t know if it has ever been tried. Although, you can do some matador tricks on the nubs of yoyojams. 
Well, I think if done wrong it could possibly throw it off balance, but it seems like a great idea!
I have been thinking about making a mod for jjy yo-yo for matador spikes, still trying to figure out a way to attach them firmly to the body. They would be fun for sure.