I know 1 or 2 of you were interested in seeing some yo-yo modding. What I'm going to show below is one of the yo-yos I finished today.
Yo-yoing has evolved significantly in the past 20 years or so. Until around 1990 all yo-yos had been fixed axle, then the first ball bearing axles were introduced. With longer sleep times yo-yo tricks became much longer and interesting. Around 2000-2001, players started messing with the traditional way that the yo-yo returns and played their yo-yo with little to no tug response. There are no limitations to what a player can do with their yo-yo now. creative tricks are the only concern.
I take low end responsive yo-yos and modify them in a way that allows advanced tricks. This usually involves cutting a groove around the bearing and applying silicone in the groove that allows a bind return. Basically the yo-yo returns only when you want it to. Sometimes I will convert the yo-yo to a larger bearing size to widen the string gap to allow more string layers. Sometimes I add weight rings to increase spin times. I did all 3 in the yo-yo below.
This is a beginner model yo-yo that is available at Toys R' us for about $15.
Here is a stock photo of the original
and the insides of the original look like this (not this yo-yo but same setup)

I cut out the original plastic hubs that housed spacers and a smaller 4mm wide bearing, and press inserted 1/2 in aluminum plugs.

Cut down the plugs to fit the larger size bearing on its 1/4" inner race.

drilling for the new axle

tapping for the new 6-32 axle
turning the long end of the plug down for eventual hubstacks, or independent spinning side members.
This is the small bearing on the post

Cutting the silicone response groove

before and after the groove

This is one of the new weight rings that i put on the rim of the yo-yo to increase spin time. The set was discarded from another yo-yo.

facing and turning down to size. Also took the green anodization off.

Cutting the rim down to fit the ring.

Ring fit on the half

Prepping to fill the grooves with flowable silicone.

Silicone installed and axle cut from a 6-32 flathead machine bolt.

After the silicone cured and side spinning hubstacks were installed, the yo-yo is complete.


Now it is a beast of a yo-yo capable of any trick anyone can throw at it.