THE most important question you will ever be asked!

[Mana]

I would probably choose the motor bike...

Cause while it is true that a horse would be able to feed itself, there are still chances that many unfortunate things could happen to it. Get hurt, sick, maybe even bitten. Zombie horse!~

And while a motorcycle can break down and run out of fuel, with all the people zombies, then you can simply get another one from a store, and its not like gas would be hard to find. S' not like a zombie would need it.

It also depends on the type f zombie... are they the slow or fast ones? Cause you can easily get away from a slow one, unlike the stupid people in the movies...

[Rascal Coyote]

Definitely the horse.

As was already mentioned, the horse can survive on grass.
The horse is an alternative food source if it comes to that.
The horse can be taught to signal danger.
The horse is a companion, so if you don't meet another person for days at least you have your horse to talk to.

Horses don't have to be taught to signal Danger, they already do that, WE have to be taught to understand the signals they give. it's in their body language and faces, you just have to learn how to read them.

pretty much all the reasons I choose a horse has been said, plus they give companion ship, which you'll need if all your friends and family have been infected and zombified.

[Tamaska]

I have to go with the Motorbike, my bike wont run away, my bike can go faster then 20km/hr, If I need to I can steal gas from any gas station, it can take a beating, It wont ever get tired (though it will need gas) I dont need to buy it shoes (the amount that you would ride that horse, it would need new shoes in a month... where are you going to find a farrier? )

The only good thing I can see with the horse is that it -could- be food for a while

[Taiga]

Oh no...not another zombie smackdown...  *eyerolls*

Where's the bike.  Screw the zombies; riding a bike is more fun.

[Laowin]

According to the zombie survival guide...
horses are dependable companions, but spook far too easily in the presense of the undead. You may wake up one night to find yourself surrounded by zombies, your ride long gone into the wilds.

Motorcycles, while requiring maintenence, are maneuverable through spaces too small for cars, fast, and while not quiet, can provide great utility.
One of the better choices is simply your average pedal bike, it's silent, and your passing won't alert any zombie hordes (unless of course they see you, but you're still on a pedal bike)
You are your own engine, in that case, so it's not a problem.

[Mayhem]

if its a mare you can hide in the wilderness and drink her milk and her blood like mongolian soldiers would while on the moove. A horse would alert you to intruders, and youd never need to go into town to refuel it. eventually the zombie plague shuld subside as the supply of fresh brains runs dry

[Merrick]

I say Motorbike and my Reversed Blade Katana, why? Because it would be totally badass!