I am designing a go kart for my college project. I am stuck with finding out how much horsepower I need. I know the centre of gravity and the total weight. Say I set a criteria that the gokart has to accelerate at some m/s^2 from there on how can I find the horsepower. I know the tyre radius and the ratio in the chain and sprocket, so I can find out the rpm I need at maximum speed. I am going to use an electric motor. Another thing is when you talk about a motor rated at for example 5 horsepower 1500 rpm does that mean that it has that hp at all rpm and 1500 is the maximum rpm? And I am totally lost on calculating the lengths of the push rods for the steering.