Is there any mods that can be done on a Duncan proyo
Any number of plastic yoyo mods could be done but there is really no point. Its a fixed wooden axle looping yoyo i does what it was intended to do well.
You can mod any yoyo in any way if you have the time, tools and skill. Or the money to pay someone to do it. I’ve made bearingized proyos and proflys that play 1a rather well.
you could drill a hole in wood at the center using a drill bit and make it compatible with the duncan bearing parts kit.
Not nearly that easy.
The hole for the spacers would have to be absolutely perfectly centered to play right. Drill press and lots of skill required.