I made a small article about this topic. I hope you guys like it and, hopefully, find it useful in the future.
Why do some yoyos feel heavier than others? (campaplusyoyos.blogspot.com)
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I definitely want to read the article again when I’m not six drinks in! I would add that the weight distribution of the yoyo is an important factor as well. For instance a rim-weighted throw takes more energy to throw but retains more torque at lower speeds so it feels heavier (to me at least).
A center-weighted yoyo is lighter on the initial throw so spins up with less effort but scrubs speed much faster and will stall on the bind at a higher spin speed than a rim-weighted yoyo which (again, to me) contributes to a lighter feeling.
But to summarize, I found your article interesting but mostly over my currently-foggy head so I want to read it again later!
Ivan
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Interesting, a bit too beyond my understanding but graspable. Yoyos are soooo complicated!
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@craZivn Wow, looks like you have much more insight than I on the physics of yoyos. Awesome 
I am thinking about a separate article for the rim-weighted and center-weighted yoyos but that will require more study, a lot more study but that would be a lot of fun to do.
@ChrisFrancz Thank you! I agree yoyos have a lot about them that can easily escape our understanding. Glad to read that the article wasn’t too obscure or overly complicated
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It’s not that some throws feel heavier……
It’s that some throws just feel lighter.
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That’s another way to see it. It’s all relative to the point of reference
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This is a huge factor. The SYFO weighs 68.5 grams, well above what my preferences are, yet it does not feel nearly as heavy as I thought it would on a throw. Contrast this with the Bettynova (around the same weight IIRC) which feels a lot heavier on a throw to me. The Bettynova has a lot more rim weight than the SYFO which matches up w/ what you said about how it will make things feel heavier.
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This is VERY interesting.
On paper, the SYFO has a conceptual density of 0.786 and the Bettynova 0.762. In theory, they should feel about the same. This is definitely something worth checking out… but I’m afraid my knowledge falls short on the topic. Still something worth investigating!
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I think the formula is straightforward, but the maths are far far beyond my brain. It’s basically a matter of leverage.
Imagine a teeter-totter. If you have a 100lb person on one end and a 200lb person on the other, the teeter won’t totter. But if the 200lb person slides inwards until he is halfway between his end and the center of the teeter-totter, his effective weight is halved to 100lbs compared to the 100lb person whose still out at her end, and the teeter-totter is balanced. If the 200lb person moves in further toward the center of the teeter-totter, his effective weight becomes less than 100lbs and the 100lb person now finds herself sitting on the ground despite having someone double her weight on the other side of the teeter’s totter point.
Essentially, the 100lb person is using all her weight to full effectiveness at this point and the 200lb person is using a fraction of his as leverage, with the rest simply adding to the overall loaded weight of the teeter-totter. So the 100lb person “feels” heavier even though she’s not.
A yoyo is like that. The more of it’s grams that can be placed at the outer edge of the yoyo, the more effectively those grams can leverage their inertia against the center of the yoyo (like the 100lb person at the end of the teeter-totter) and the yoyo feels powerful. But inertia works both ways. When those grams are not spinning, it takes more effort to get them moving so the yoyo also feels heavy.
If the grams are concentrated inboard toward the center of the yoyo, it’s like moving the 200lb person toward the center of the teeter-totter. There are the same amount of grams as the rim-weighted yoyo but they cannot use their inertia to full effectiveness since they’re closer to the center of the “lever”. So the yoyo takes less effort to spin up and feels light, or “floaty”. However, with less effective inertia, the floaty yoyo will succumb to drag more readily and so does not feel “powerful”.
Anyway that’s how I imagine it. So I’m guessing there’s either a lot of trial-and-error, or some really fancy formulas that manufacturers use when deciding how to distribute the weight to make the throw feel just right!
Ivan
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It’s all in the hands.
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Lovely explanation!
I was thinking that if we take into account the material of the yoyo, then it becomes even more interesting. Titanium, for example, has more density and it’s harder than Aluminum, which gives more freedom when distributing the mass because you can make some walls thinner without the risk of having a flimsy body. I imagine this works both ways too, if the material is too hard and dense (like tungsten) then a 66g yoyo would need to have walls so thin it would be brittle and the yoyo would probably shatter on impact.
This is fun hehe.
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Thanks! And I agree, the material used is as important as what’s done with it for sure! I know I’ve said this on the forums like a million times but I’d love to see what a brass yoyo would play like. And how it would sound! It seems like brass would be a good material to try, as it can be made thin and is durable and dense.
Or bronze would be sweet as well.
Ivan
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Beryllium copper.
Your welcome.
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Brass has been used on quite a number of throws already, though not full-sized. If you want a feel for how yoyos made out of the material plays, check out the Rain City Skills Loonie, Loonie American Edition, Luo Yicheng Kun and the Mini Panzer.
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Awesome right up, I love how in depth you went on your journey. To throw one more curve ball, look into airflow and torsional drag. Yoyo’s can act similar to a wing but in some very complex ways. Hold your hand out flat to the cup and watch it suck in, and feel the air shooting out in a 360 from the gap post compression, this effect can change how a throw feels on the string substantially. Modular let’s you play with this effect a lot
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One of my favorite things to do is throw a sleeper right above my bare toes and feel the tiny breeze it makes! Or hold it up to my ear to listen to the sounds.
Have you ever experimented with adding dimples to see if it increases spin time, or adding notches to make the yoyo hum like a tone ring or whistle? I think the world of musical yoyos is an untapped market.
@Hanker That Toonie definitely looks sweet! It looks like those yoyos are taking advantage of the density of brass to make the yoyo smaller, whereas I’d like to try one that’s larger with thinner walls so it resonates kinda like a bell when spinning on the string.
Ivan
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Uhm, the Toonie is made of aluminium with stainless steel rims, not brass. Yes they are, to more easily distribute the weight and give the yoyo sufficient weight to be stable. Ah I see, but I think a full-sized brass yoyo would be much too heavy for a lot of people. Considering that full-sized stainless steel yoyos are already 66-68g with the walls as thin as it can be and brass not being as tough as stainless steel, I think you would end up with a pretty heavy yoyo, maybe about 75g or so. In addition, brass is denser than steel as well so the yoyo is just going to be heavier. It’s going to take a certain kind of yoyoer to like such heavy yoyos.
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Gah, sorry I meant the Loonie! Mis-typed.
What you say about brass makes sense, explains why no-one’s made a large one. It doesn’t stop me from wanting one, even if it’s like a 66% size or even a little one with thin bell-like walls!
Maybe if I dismantle two of those round bicycle bells, solder a bearing seat into the middle…
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Ohhh.
Well, looks like Rain City Skills or Topyo would probably be the first to release such a yoyo, or even consider it, given their previous yoyo releases. Try speaking to Jeremy, I bet he can make your dreams come true.
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