I have a 2002 fuel injected springer that spits and sputters like I'm running out of gas when the gas tank gets to about half full. What's up with this?

 

Somewhere, your gas tank has a one way vent to allow air into the tank, but prevents gas from escaping.
If you can't get air into the tank to fill the vacuum created as you use gas then the pressure eventually prevents gas from exiting the tank.
to check for this, when it starts sputtering, open your gas cap, if that fixes the problem, then there's something wrong with the tank venting.

 

Sound like the line inside the tank has a small hole in it .Very common problem. Pull the gas cap off and turn on the ignition and listen for gas spraying inside the tank.

 

Complete a fuel pressure test. Darkside is probably right, need to replace the fuel line inside the tank. Dont forget the gasket and 10-1311D screws.