The Story of Graviton

The story was written by Tony Sung: 

It was summer break in 2021. While I was getting ready for my grade 12, Philip sent a design of titanium rim bimetal yoyo to our group chat. 

I felt very excited about this design, that our team is finally making a titanium rimmed yoyo. Our manager Philip had eyes on my effort as a yoyofriends player, and he let me use this design to make my signature model. It was the most exciting thing ever happened to me as a player and a designer. 

First, I had to choose specs for this yoyo. My standard of an impressive player is people who can coordinate different elements without any delays/hesitation, and are not limited to using other body parts. Therefore I’ve been looking for a yoyo that can assist me to hit many tricks more casually. This couldn’t be done by just using a wide yoyo, because the yoyo could land on the wrong strings or can hit my hands. Moreover, my hands are almost “objectively” small, compared to my peers, which makes hitting the chopstick tricks a little harder for me. 

I chose the range of weight in between 64.29 to 65.15 grams. I was going to make it around 66grams at first, but that would make it harder to execute zoning combos and laceration consistently. I couldn't just make it lighter because I was worried about the yoyo spinning less longer, but then I could confidently make it lighter after watching people doing complicated tricks consistently with light a yoyo, such as Junsang Park, Shion Araya, Jonathan Sitangang, and Ahmad Kharisma. 

I had to spend tons of time on trapeze width(or effective width). Trapeze width is the width of the yoyo, where you can actually land the yoyo. 

You can execute tricks more effectively as the difference between the overall width and trapeze width gets closer to zero, but it also makes yoyo too sharp, which would even weaponize them. So I spent almost 2 weeks choosing the trapeze width that would work for me the best. 

The final spec I decided on is 46.99mm in width by 55.35mm in diameter. These specs were chosen after trying various tricks with a bunch of different yoyos. 

Then I moved on to the designing part. The outer rim is exposed to bigger risks of rim shift, which is also caused by dropping or dinging. I found some people using outer rim yoyo for 3a and 5a(which have higher risks of dropping or dinging) these days, such as Alex Hatori, Takeshi Matsuura, Sora Ishikawa, or Miggy Hizon. However, still, there are a majority of players who prefer to use the inner rim to prevent these issues, but I wanted to go with the outer rim which gives more power. So I maximized the surface area of the joint, to hold the rim tighter. 

Then I finally began to draw the profile. I wanted my yoyo to look friendly, yet distinguishing in some parts. 

I design tons of models carefully for each project. Especially this one would be my first signature yoyo, so I put more of my effort just as I’m actually prototyping all of them, then I chose my favorite among the best designs. I was considering putting a fingerspin zone as well, but I decided to make them more oriented to powerful spin. 

The first prototype was very powerful. Fits really well for long and consistent horizontal combos. Plays awesome for complex 1a combos and insane 5a bangers. The wall thickness is relatively thicker than other 7000 series yoyos, and has a 10mm long axle. This prevents serious damage or distortion of yoyo which can be caused during 3a or 5a play. Nevertheless, It lacked floatiness, and the components of the design were looking awkward. 

The second proto has less cuts, in fact I made most of the cuts more organic. Instead of reducing awkward design components from the first prototype, I added more dynamic designs to make a better balance. Also rims are about 2 grams lighter on each side, and overall weight has slightly increased to prevent loss of spinning time. The groove around the hub improved the fingerspin as well. 

I let people use both of my prototypes at the Yoyo Toronto meet up. Most of them liked the floaty second prototype better, but some liked the first one more, which is more powerful. I want as many throwers as possible to love my signature yoyo, as well as keeping the identity of this yoyo. So I began to calculate the “Moment of Inertia”, or MOI for short. 

MOI shows the value of the intensity of conservation of a spinning moment. They are decided by the weight and size of the object. In simple words: a higher MOI gives more powerful yoyo, and a lower MOI gives more floaty yoyo. But we don’t only care about the numbers that MOI shows, but we better care a lot for the balance between the size, mass, and the MOI. 

I found the MOI value of the first and second prototype for reference. I felt interested that the 1st proto has less MOI on the rim (even though the rim was heavier than the rim of 2nd proto), but more MOI on the body which gave higher overall MOI. and I found out that the rim has less MOI than the 2nd proto because the shape of the rim was cut toward more inside. So I put the shape and MOI of the body of the 3rd prototype in between, except the MOI of the rim is higher than ever and the weight is lighter. 

And it was a “Huge Success”. The yoyo got its power while minimizing the sacrifice of floatiness. All the specs and the shape show an amazing harmony, just as they were chosen for each other. The product is worth more than 14 months, my time for the Graviton. 

I drew the logo by myself as well. 

I felt I had to choose the name by the time I got the prototype, and I spent a fair amount of time coming up with the name “Graviton”. I had some other candidates: “Private Jet”, “Buse À Miel”, “Bald Eagle”, and “Mind Hack”. Then I found the word “Graviton”, a theoretical particle that mediates gravity. This drew my attention, and I loved it that graviton only exists as a theory, which sounds surreal to me. Also, graviton can be a metaphor for “a yoyo that mediates sensation”. It also corresponds to “Tachyon”, which is also a theoretical particle.

The circle in the back is just for coolness, and it didn’t have any meaning. Then I called it a massive black hole, and finally, I called the circle, the graviton, the name of my yoyo. The letter on the circle says Grit, from “GR” av ”IT”, which means strong courage or determination to overcome difficulty. 

There are lots of amazing yoyos, and I’m confident to introduce Graviton as one of the best yoyos ever made. Weights are sufficiently distributed to every part, size and shapes are good for 1a, 3a, and 5a. Try simple combos, try ridiculous bangers. This yoyo is the embodiment of an all-rounder. Hope you enjoy your time with Graviton! 

The first run is available on yoyofriends official store. Comes with titanium axles and excellent concave bearing. Hope you enjoy your time with this yoyo!

Here are the details of Graviton:
Weight: 64.7grams
Material: 7068+Ti rings
Diameter: 55.35mm
Width: 47mm
Gap width: 4.43mm
Axle: M4*10mm
Bearing: Concave
Pads: 19.2*14.2*1.2mm
Price: 179.99/set

The box contains:
1 x yoyo
1 pairs x pads
1 x string
1 x graviton sticker
1 x yoyofriends sticker
1 x grey iron canister
1x titanium axles（M4*10mm）