The BMX stem plays a big part
The purpose of the BMX stem on a BMX stunt bike, or a BMX freestyle bike as its also called, is to attach the bar to the fork. It is in the stem the compression is made.
The BMX stem on a BMX stunt bike plays a great factor in how the front end of your BMX stunt bike/ freestyle BMX bike is going to feel. The primary difference between the BMX stems for BMX stunt bikes aka BMX freestyle bikes is the length and the increase of height. Height and length are both factors that can affect how fast the balance point appear on the bicycle. A short stem will give a more responsive front on the BMX stunt bike, where a long stem will give a more slow and controlled front. The BMX stem determines how far away from your chest the bar is. A short stem combined with a fork with a short wheel offset makes it easy to get up on the front wheel.
Do you need a top load or a front load stem?
There are two ways the bar can be mounted on the stem, top load mounting and front-load mounting. On a frontload stem the bar is mounted on the front of the stem. A frontload stem is often preferred by the taller riders since it places the bar further away from the rider.
On a top load stem, the bar is mounted on the top of the stem. The top load stem is taller than the front load stem. A top load stem is recommended if you prefer to ride with a taller bar.
Take note: Be be sure that the BMX stem you are looking for is the same size as your handlebar.