Question: I have a spinning gear on my website displayed with this code:

```html
<link rel="stylesheet"
 href="https://maxcdn.bootstrapcdn.com/font-awesome/4.5.0/css/font-awesome.min.css"/>

<i class = "fa fa-cog fa-5x fa-spin"></i>
```

Personally, I think that the speed of the gear is too fast. Can I modify it with CSS?

Answer: 
Not necessary to use an own animation or class definition. The speed of any css animation can control by the [animation-duration](https://developer.mozilla.org/en-US/docs/Web/CSS/animation-duration) css property. Simply use:

```
.fa-spin {
  animation-duration: 3s; // or something else
}

```

As higher the value the lower the animation speed.
Similar to the Michael Laszlo's answer. This is what I use to make it faster for fa-refresh as the fa-spin by default is very slow.

```
.fa-spin {
 -webkit-animation: fa-spin 0.75s infinite linear !important;
 animation: fa-spin 0.75s infinite linear !important;
}

```

I use !important so that I control the specificity :)