Tomorrow, you’ll be looking at tires differently. Why do bigger tires grip?

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明日からタイヤの見る目が変わる。なぜ太いタイヤはグリップするのかGet unbeatable grip with thicker tires

Everyone wants to ride on a tyre that has a lot of grip and not have to worry about slips and falls, rather than being jumpy with a tyre that has a lot of grip.
And I'm not talking about a special kind of "I want to reduce my lap times on the track"; I want to feel good on the road.
That's the kind of thing that makes you want to make a swift turn without worrying about slipping and mocking at an intersection.
Maybe it includes a desire to run faster than that guy you're always running with, but then again, we're talking about public roads, so it's not about lap times.

So when choosing a tire, the most important things to consider are "durability", "wet performance", "affordability", etc. ......
You're choosing tires that grip as much as possible (or so it seems) in that situation!
Yes, how good the grip looks.Thick as possible.You can't do it!

WebiQ is here to bring you a little happiness and motorcycle knowledge.
In this article, we're going to talk about why thicker tires are high grip.

common misconception

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Do you think that the bigger the tire, the better the grip?
The wide ground contact area of the thicker tire makes it grip like it's sticking to the road!
I think that's what many of you may be thinking about.

In fact, there is a major pitfall here.
Contrary to the image, a tire is aMore ground area does not change the grip.of. (!)

Thicker doesn't mean better grip.

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No way! I know what you're going to say.
In fact, I'm running the biggest tires that the regulations allow for in a race.

However, the tires grip completely according to the laws of physics.
And the grip is the frictional force, and as we learned in junior high school, the frictional force is determined by "load" and "coefficient of friction".

Hmm? There's no 'ground area' to indicate thick and thin, is there?
That's right, the ground contact area of the tire is not directly related to its grip.
If it's the same bike, with the same rubber tires.No matter how small or large the tire is, the grip is the sameIt is.

As the vehicle is pressed against the surface of the road by the cornering force, a greater load than the weight of the vehicle is applied to the tires, giving them more grip than if they were simply rolling in a straight line.
In that case, too, the thickness of the tire is irrelevant, and the increase in grip under load is the same.
It's not as simple as saying that loading a big tire will give you more grip than loading a thin tire.
There are actually more complex elements, but I won't bore you with them here because they are difficult to understand.

So why do you wear bigger tires in a race?

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The reason for this is that we want to increase the "coefficient of friction", which is the other factor besides the load that determines grip.

What I mean is: ......

    1. You want to use soft rubber to increase the coefficient of friction.
      (You want to use rubber that has a coefficient of friction that sticks to the road surface.)
    2. However, if you use soft rubber, the softer rubber will be reduced at an amazing rate.
      They're running out so fast, they don't last until the end of the race.
    3. To prevent this, the ground area must be increased and the load per area must be reduced.
    4. To reduce the load per area, you can increase the area.

    The result of this repetition is that the tires have become thicker.
    It's not because it's thicker that it has a better grip, but because it's thicker to prevent wear and tear as a result of using rubber with a better grip.
    The order is reversed.
    It's complicated.

    As a side note, not everyone likes to wear the biggest tires in a race.
    Soft and fat tires have more rolling resistance, so it's harder to get top speed, and the ground contact point is off-center while cornering, so you'll have to shift your weight around a lot in order to balance, and you'll have to make a sessy move on the left and right hand turns.
    But even with the negatives, the improvement in cornering speed outweighs the benefits, and the result is better lap times, which is why we use bigger tires.
    If you can get the same cornering speed and have the same durability, though, the tires should be thinner.

    As a result, the bigger tires are high grip

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    It's not because it's thicker, it's because it's made of softer rubber that you have to make it thicker.

    For example, if you need extremely short driving time, it's best to go with thinner tires with the same rubber as the thicker, high-grip tires.
    The tire itself will be lighter, less aerodynamic drag, and even grippier than a larger tire because of the increased load.
    However, the tire will be at the end of its life in the blink of an eye.
    In reality, the grip does not improve in proportion to the load, but it's hard to understand so I won't mention it here.

    A vehicle with a larger stock specified size means that the vehicle is designed to have some durability while still providing high cornering speeds with rubber that is soft enough to demand that thickness.
    The thicker tires are a sign of high performance, as you might imagine.

    summary

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    Basically, bigger tires are high grip.
    However, it's not because it's thicker that it's high grip.
    I used a soft rubber for high grip, but it was too fast to reduce the surface pressure, so I had to make it thicker to reduce the surface pressure, which was the correct answer.
    It's a mistake to say that the friction force increases because the ground contact area increases.
    In other words, for the same rubber, a thinner tire will have a higher grip, but in return, it will wear down faster.

    If you are able to wear thin tires with wheel diversions, please try it out if you have the opportunity.
    If you're not aiming for absolute grip, such as with touring tires, you may find that thinner tires give you more grip.

    Also, each car has a different "expected load" and "expected rubber" so there is no such thing as a "thicker looking car with a larger displacement that has more grip".
    It's possible to get better grip on a heavy 100mm wide minibike that's tightly throttled and overloaded than a lightweight supersport that's 200mm wide but not fully loaded.

    Is it possible to have a high grip on a thin tire?

    This is possible.
    We can use a hard rubber (compound) that does not expire quickly after heavy loads are applied, and we can use that hard rubber to increase the coefficient of friction by applying heavy loads.
    In order to increase the load per ground area, you need to make the tires thinner ......, which is the exact opposite of a thicker high grip tire setup.

    So why aren't those tires available because if you use thin, hard rubber to make a high grip tire, it will be vulnerable to load changes.
    Theoretically, high grip is possible even with thin tires if heavy loads are applied continuously, but if the load is released in a small gap in the road surface, the tire will quickly slide.
    That's what happens when you rely on extreme loads, as per the laws of physics I wrote in the first paragraph.
    This is why "thicker and softer" tires are more resistant to sudden loss of grip, even under slight changes in load.

    This is the reason why 4-wheeled vehicles can dramatically increase their cornering speed by using the wing to increase grip and cornering speed by using large downforce (i.e. load), but if the downforce (load) is suddenly lost, such as when passing through a large gap, the vehicle can spin out of control.
    Also, in a four-wheeled race on a snowy road, you can't expect rubber friction to stick to the road in the first place, so you try to increase the load and increase the grip.
    As a result, there are some genres that run on incredibly thin tires.

    Well, it's deep.
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    If it's asphalt, they have tires that are thicker to just barely the width of the body, but on snow, the tires are thin enough to merge in.

     

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