Yes, for plane changing for sure, but there are significant directional speed changes too.
Not buying it, but thatās ok.
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I think what you contend, is that if you had two different yo-yos where all of the specs were the same, except for weight distribution, the quickness of the directional change would be the same for both yo-yos?
Yes 
Itās what physics tells me.
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This makes sense to me. I suppose that if ācontrollable instabilityā (i.e., āveeringā the yoyo on purpose) is a desirable trait, then bimetals are probably not the ideal choice.
It can be desirable, in that these are toys, and that can make them more fun if youāre in the mood for that kind of play. It can also help you develop your ability to make those adjustments during play, as the yo-yo responds more readily . Itās usually more of the ability to get the yo-yo back on plane, than to get it off plane, but it could be both.
You said>
Iām saying they arenāt maneuverable, just that they most likely donāt have the same level of maneuverability that a monometal can have.
ā¦I think you are missing a word.
Your first phrase should say, āIām not saying they arenāt ā¦
Not,ā Iām saying they arenātā¦
Correct, Doc! Thanks for point that out.
I meant to say āIām **not ** saying they arentā.
Is this one of those āon averageā types of assertions? You know, where the original assertion is trying to say that āon averageā bimetals āmost likelyā donāt have the same level of maneuverability as monometals? If so, how does one determine what the āaverageā is, what āmost likelyā even means quantitatively, and how one would even go about measuring something called āthe same level of maneuverabilityā?
I disagree.
Hereās an example:
Hold a 200g weight in your hand with your arm out to the right side of you. Then swing your arm from the right side of your body to your left then immediately back again.
Then, fix that same 200g weight on the end of a 50cm stick straight out from your body and do the same motion with your arm in the same position as before. You will feel it resist your movement more because it is further away from the point of force applied to it.
This is the same concept that is happening with a bimetal yoyo. The bulk of the weight of it (the rims) is further away from the point of where the force is applied to it ( the centre of the yoyo) therefore it resists your movement more and this can be easily felt.
Perhaps this isnāt the best example to give, but it still explains the concept.
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In your analogy, the motion of moving the 200g weight is analogous to the throw/return (unwinding/winding to start/stop spin), not the translation of the entire yo-yo in space (which would be the combination of your whole arm + stick + weight)
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I believe it still illustrates the concept effectively enough. The directional change becomes harder when the majority of the weight is further away from the point where the force is applied.
Think about it. Your shoulder is the axle, the 200g weight is the rim-weight placement. Youāre describing the spin changing speed around the axle, not directional change (translation) of the whole yo-yo. You would have to add a giant rope (yo-yo string) to the person/stick/weight (yo-yo) to represent it all.
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I didnāt mean swing your arm a full 360 degrees, just from one side of your body to another.
In fact just hold that stick with the weight on the end and do any kind of random and quick directional change and youāll see itās harder than if you are holding the weight in your hand.
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In your example, youāre putting a torque on the mass by pushing on it away from its center of mass. In a bimetal yoyo the center of mass should be perfectly inside the middle of the axle/bearing, just as it should be in a monometal. Pushing/pulling on the string applies the force pretty much directly on the center of mass. A more accurate analogy would be to place two 100g weights on the end of a mass-less rod and hold it exactly in the center while moving it around.
Moving a bimetal along a string isnāt any different from moving a monometal, provided they have the same mass. Most of their difference in feel is going to be during the throw & bind, where the difference in rotational inertia comes into play big time.
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Yes I actually thought of this one earlier and should have used it.
I disagree. Where the majority of the mass is located affects the movement significantly.
If this were true, wouldnāt a spinning bi-metal fall more slowly if you dropped it?
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Yeah I get that, Iām just saying youāre describing rotational change (around the axle of the yo-yo) and not directional change (translating the whole yo-yo through space). Again, your shoulder is the axle and the weight is the weight-placement/distribution, right?
@MarkD is giving the example of gravity (a force) being applied to two different yo-yos with the same mass. Theyāre going to accelerate down at the same rate. Substituting another force like the tug of a string wonāt change that.
@FiveIronBrian and @MarkD are correct. You are talking about a change in the translational momentum, not the rotational/angular. The moment of inertia of a yoyo describes how the mass is placed radially. It should not have an effect on translational momentum which is only in terms of mass and velocity (mv), not moment of inertia. Your example with the masses being held out at different radii only applies if you are spinning, they should not be any harder to move if you are walking back or forth if you hold them away from yourself because your center of mass is still the same. It sounds like you feel a subjective difference in the maneuverability, which is understandable because yoyos all have a feel that is totally subjective and individual.