Bimetals with rings pushed in?


I’m seeing these new bimetals where the rings are pushed towards the center instead of all the way on the outside, for example the edge and space cadet. I’m curious if this is an effective design because doesn’t that go against the whole point of a bimetal - pushing weight to the edge?


¡¡¡MY GUESS!!! is that putting it there will give it a good balance of speed and stability. It is still far enough to the EDGE (pardon the horrid pun) to get great stability, but still leaves some center weight, making it able to change directions easily. Like I said, this is my guess…


The centered rings aren’t really anything new, Yoyojam had been doing this all along. The H3X, Diamondback 2, and Karma all have centered rings which give a nice balance of stability and a dash of speed.


Gumball; you forgot a few of Mickeys signature yoyos also have rings away from the edge.


Actually pushing the weight to the edge isn’t the whole point of a ‘bi-metal’. Somebody may have started that misconception but that is not the whole purpose.

First of all bi-metals don’t always have the weight ring on the outside.

Bi-metal simply identifies a yoyo boast consisting of 2 metals. Bi-metal does not designate the placement of the rings.

And bi-metal does not identify the specific purpose of the secondary metal utilized within the design.


But then what is the point of having an additional denser metal?


I believe it would be simply to change the moment of inertia of the entire yoyo… (Me right?)


The point of having the additional denser metal is to allow the designers the capability to focus weight more specifically to accomplish various enhanced performance parameters.

The Luftverk Fulvia BMT-R for example; weighs in the mid 60’s. About 40 grams(of the 60+total grams) are entiredly rims! 2/3rds of the Yoyo is All rim weight. The Titanium cores only weigh about 10. Something grams each.

The 2Sick Knight has the rings embedded into the sides; with main body metal on both sides of the rings.

The Something: Anglam, Anglam CC, Anglam2, Phaser, etc.;have the rings pressed in the underside of the rim.

The Yoyojam H3X, the Yoyofactory Space Cadet and Edge(and several other yoyos; have the rings inboard and down slope of the outer rim edge.

The: Firrox, Rave, Rainfly, Slasher, Nightmare, Igloo, etc.; have the weight rings on the edge.

They are All bi-metals and they All play differently within the groups and compared to each other.

Because every recipe is slightly different.

…So the ‘point’ of bi-metal yoyos is simply to allow the makers more latitude in performance tuning.

And to a much lesser degree; to also expand visual potential. Some yoyo designs result in strikingly different appearances. Just like cars; some people go for: performance, some go for looks, some have to have both.

Some yoyos look better than they play. And some yoyos play much better than they look🤓

So there are valid points to Bi-metals and Tri-metals, etc.

…Yo-yos, Pool cues, baseball bats, bowling balls, golf clubs, tennis rackets, mountain bikes, surfboards, skateboards and a few hundred other items are all subject to ‘weight tweaking’ to achieve various results.

Weight shifting in yoyos not new magic. It is simply the evolution of performance functionality.

Something like that…

PS; A certain percentage of folks actually are not thrilled when I light a candle in a dark room.
I am compelled to increase luminosity occasionally simply because I know the World turns a little faster when ignorance is replaced with knowledge.


That of the Space Cadet and The Edge is the best point where increasing the weight of material … provides benefits in terms of stability (unlike on the rings ring) and spinn … YoyoJam taught with his yoyo! the Phenom fully deserves the name it bears !!! and that he knew it too Heath Vizier, for those who possess it, try to palpate the cups of the TI-Walker and feel where it is the thickest!

(rizkiyoist) #10

As far as I know (which isn’t an expert per se), putting weight there will reduce the tendency to have ‘throw vibe’ because the weight is closer to the center and not too far wide (width not diameter), it’s inherently more stable.
This is apparent in modern plastics like Speedaholic. Since plastic is less dense than aluminum, to get the amount of kickback similar to aluminum one has to either increase the diameter, or put the weight wider which is the case with Speedaholic, which makes it prone to vibe. This is also the case with some undersized yoyos like Adegle Rhong-To.
Basically there is a limit on how you can make the yoyo wider vs the diameter, and going over the limit will make the yoyo less stable because the weight at the tip will get thrown out and it wants to spin width wise (see picture below).
If you need to move the weight on the rim YET still stable, the yoyo has to be imperial shaped. This is the best possible way to put the weight on the rim and is inherently stable, BUT since the wall will be very high it will compromise balance anyway (more tilty), and it will be difficult to play since it’s not wide enough. If you move the weight on the rim AND want a wide yoyo, the wider you concentrate the weight on, the less ‘self balancing’ the yoyo is, since not only it wants to spin along the axis, it also wants to spin sideways against the direction. At certain point when the yoyo is way too wide, it will vibe so badly and become totally unplayable regardless of how good your machinist is, because it wants to self balance in the wrong direction (see picture below).
I forgot what this is called, ‘ping pong racket effect’ or something.
And to answer the question, the ring placement is there to make the yoyo inherently more stable, which is not possible to be made only with mono metal. The benefit of the denser metal is still there.

(InvaderDust) #11

Technically any OneDrop that has side effects are BiMetal. :slight_smile:

(rizkiyoist) #12

Yep, one can even see the side effect as the ‘base’ yoyo and the body as the rim.

Even further, technically again, the bearing, axle, and the halves themselves are of different metal.

({RTD} alecto) #13



Many manufacturers are opting for the choice of weight rings in the outer part of the shell (rim) for ease and speed of implementation, others to experience to the utmost the potential of processing of certain materials, the greater example is:

I personally do not think that’s the right way, both for obtaining the best performance for both large amount of risk to which we encounter … this is because the concept of workability of a material does not match the object’s usability obtained.
from the photos you can see what happens to a titanium grade 5 shell with a minimum thickness of 0.25mm impacting on earth (then, the titanium allows workability even at these thicknesses)
… Fulvia BTM has minimum thickness of 0.45 mm, with all the weight concentrated in the outer steel ring … the event of impact, in the best hypothesis, its shell us would bend as a sheet of paper … its fragility is also demonstrated by the large number of broken shells in the process of assembly of the rings. of course a good experiment but not the way to get a usable object in tranquility and with superior performance (until now I have not read feedback to that effect)


Of course there is also the benefit of having a more grind friendly surface available for palm grinds.