Here are some tricks you can do to save on time throughout the run that I've found over the years I've seen Super Tux Kart:

Starting the Race:

If you pause with escape after about a second after the map finishes loading, you can cause the race countdown to start early. My hypothesis is the game spawns the bird which is supposed to bring down the countdown light, but pausing it makes the game assume the bird is already done its animation, causing the bird descent animation to be skipped.

Drifting:

It is always good to at least have yellow drift since its free speed and with practice can be done on any straight path. I've gotten a lot of time to practice it, it's awkward at first but always a time saver. Red drift is always better than yellow drift if you can route in ways to fit it in, but bear in mind having no drift speed at all slows you down.

Item usage:

The Fly Swatter, Bubble Gum, Parachute, and Time Bomb are all mutually exclusive of one another. For example, if you have a time bomb, that will be overridden by a parachute, which can also be overridden by applying gum. The only exception is a fly swatter over a time bomb, in which case you will lose the fly swatter afterwards.

The parachute can be ended early by slowing down sufficiently enough. It basically has a force-end speed that eliminates the parachute should you ever go some speed below the speed you got the parachute at. If you've already run over a zipper with stacked boosts just before getting the parachute, you may not even need to slow down at all.

The bouncy ball (which I like to call "the Impending Slam Jam") can be stopped or avoided a couple of ways:

• You can cause the bouncy ball to collide with a wall or ceiling. The bouncy balls explode on contact with surfaces that are not floors.
• You can block it with bubble gum.
• You can throw an attack item at it. If it collides with the bouncy ball, it'll explode.
• In some rare cases, you can outrun it. Red drift + Nitro is enough to keep up with the bouncy ball when it's in rapid bounce mode. Adding a zipper with any combination of Drift and nitro can outrun a bouncy ball.
• In some even rarer cases, you can confuse the bouncy ball. An example is Candela Town's pair of paths down the long road.

World Map:

While you can teleport to other stages, track warps right next to each other (Like the four tracks off in the desert or the three in the mountain) are fairly slow when clicking the map because it's easier to just accelerate and go instead of taking the time to click.