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52 votes
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What is the purpose of these “partially filled in” locomotive wheels?

Those are counterweights. They work exactly the same as those lead counterbalance weights on the wheels of your automobile. If they left those out, then those connecting rods and bearings would ...
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29 votes

What is the purpose of these “partially filled in” locomotive wheels?

Those are balance weights against the joints used for the rods linking the wheels together.
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27 votes
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Why do car wheels have holes?

Car wheels have holes mostly due to weight and cost considerations. Each hole is a chunk of material that you aren't wasting and weighing down the wheel with. As another bonus, the holes help with ...
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19 votes
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Why do cars turn by turning the front wheel?

If you were going to turn left 90 degrees, without turning the wheels, then you wind up dragging the wheels sideways while you turn. 16 seconds into this video shows exactly what I'm talking about. ...
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19 votes

Why do car wheels have holes?

Many of the answers so far have mentioned that part of the purpose of the holes is weight reduction, but most of them don't express why weight reduction in the wheels is important. There are two ...
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17 votes

Why do car wheels have holes?

Mainly to reduce weight. A car's handling characteristics are improved by keeping the 'unsprung weight' (the weight of the car not isolated from the ground by springs i.e. the wheels, axles, hubs, ...
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15 votes

What is the purpose of these “partially filled in” locomotive wheels?

The oversized counterweights on the second set of wheels are to help balance the additional inertia of the pistons, piston rods and crossheads, which are directly connected to the wheels on this axle. ...
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  • 151
12 votes
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How can I calculate the power and torque required for the motor on a wheeled robot/vehicle?

I laid everything out so you should only need to read it from top to bottom and look backwards for variables, never forward. I also tried to lay it out so hopefully you know where everything is coming ...
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11 votes
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Is a chair with N+1 wheels ever less stable than a chair with N wheels?

Assuming all the wheels are evenly spaced on the same circle, then more wheels is always more stable than less wheels. However, there is diminishing return as the number of wheels gets large. The ...
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7 votes

Why do cars turn by turning the front wheel?

The main reason is because when a car brakes/decelerates, the load is reduced on the rear wheels and increased on the front wheels. If your car was exclusively rear wheel steering you would lose ...
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  • 7,489
7 votes

Why do cars turn by turning the front wheel?

While it might be possible to design a rear-wheel-drive car in such a fashion that the front wheels basically operated as casters and the steering was controlled by driving the rear wheels at ...
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  • 349
7 votes

On a car with all-wheel drive, how does the engine provide the angled front wheels with power?

You could also include front-wheel drive in your question. It would be enlightening for you to look at what radio control rock crawlers do. It has much of the excess of a full-sized car stripped away. ...
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  • 3,325
6 votes

RC car steering mechanism type

The key feature is that the steering has Ackerman geometry This means that the steering arms coming off the back of the hubs are connected to the steering linkage at a point inboard and behind the ...
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6 votes

Why do cars have beveled tires?

When a car turns the sideways force will pull the outer side under the rim. A angle sticking out will get worn off quite quickly. Also if a tire isn't properly inflated then the walls will bulge over ...
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6 votes
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What makes scooters unstable at high speeds?

As has been mentioned above the size of tires plays a major role. Let's assume the manufacturer standards for a wheel after improving the shaft allows 1/100 mm of play. This much play would encourage ...
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6 votes

What is the purpose of these “partially filled in” locomotive wheels?

These counterweights are found on all piston-driven steam locomotives (not just Soviet designs), and even a few types of diesel locomotive using connecting-rod drive. As other answers note, their ...
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  • 161
5 votes

Why do cars have beveled tires?

To add to @ratchetfreak's answer, there 2 more reasons: 1. Manufacturing process It's much easier and more reliable to make a continuous surface that us bevelled, that an angled surface from rubber ...
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  • 181
5 votes

Why do car wheels have holes?

The holes in wheels serve a few purposes. They reduce the weight of the wheel itself, although not by much. The holes in those particular wheels actually appear to be adding rigidity and strength to ...
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5 votes

Is a chair with N+1 wheels ever less stable than a chair with N wheels?

I think the "health and safety" regulation about 5 wheels is a compromise between stability and cost. If your weight is on the edge of the chair seat and the chair has only 3 wheels, it is much less ...
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  • 12.5k
5 votes

Why do cars turn by turning the front wheel?

The Jeep Hurricane has four-wheel steering that allows it to pivot 360° without moving. But it's very complex and expensive. I would guess that skid-steer systems in general are heavier, bulkier, and ...
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  • 151
5 votes
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Reason of Using exactly 5 Wheel Studs per Wheel

On reason is that die cast (alloy wheels) generally have an odd number of spokes. This is because having directly opposed spokes causes problems with residual stress distribution as the casting cools ...
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4 votes

How to make wheel rotate slower in one direction than the other?

Sailboat 2-speed winches do exactly this. Winding the handle clockwise directly engages the drum via one ratchet, and when you wind it anti-clockwise a different ratchet engages an epicyclic gear. ...
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4 votes

Why do cars have beveled tires?

If you press a cylinder on a flat surface the contact pressure concentrates on the edges and becomes very high. We call that edge stress condition. If the cylinder has a profile (curved instead of ...
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4 votes

Why do car wheels have holes?

It's for airflow to allow for extra cooling. In most situations, that extra airflow isn't going to help. But when you're doing heavy braking coming off of a mountain, it can make the difference ...
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4 votes
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Why is a cart with swiveling casters in front stable, but not if the swiveling casters are in back?

Consider what happens in front wheel steering, such as an automobile: Turn the steering wheel slightly clockwise. The front wheels each turn slightly clockwise. Their rolling action causes the wheels ...
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4 votes
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How to get a wheel pump to deposit water near the top of the wheel?

Consider an alternative to the current placement of the cans. The image above from the Pinterest web site, UN Food and Agricultural Organization shows a wheel in which the cans (bamboo tubes) dump ...
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4 votes

Why caster angle causes wheels to self-center?

There are two different concepts there: caster angle caster trail at wheel center Figure Caster offset Both the angle and the offset are important to determine the castor offset and the castor point ...
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  • 22.7k
3 votes

Why do car wheels have holes?

Yes I agree, the "moment of inertia" is a factor in making "spoked" wheels, the holes in pressed wheels will reduce weight, and allow circulation. The truth is, for this kind of wheel, it is largely ...
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  • 131
3 votes

Can a six-wheeled F1 car have a better acceleration profile than a typical F1 car?

The complication here is that the simple relationship between wight (or downforce assisted equivalent) coefficient of friction and traction is only true up to a point and in performance tyre that ...
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3 votes

How to add traction to a wheel?

Depends on a lot of factors, like what surfaces the car is going to go one, the size and weight of the car, if wheel-well dimensions are a constraint, etc... In general however, if you're trying to ...
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