Motorcycle Repair: 1999 Sportster 883 popping and dying, sportster 883, baffles

Question
First off I will tell you exactly what it is doing and see if you can help me out. I will first start the bike and it will run great for about 3-5 miles. After that time the bike starts to pop and dies. If i wait and try and start it again it will either start right up again but once and a while it will pop and have a hard time starting again. I have changed so far plugs, wires, air filter, we have tried different jets, and it does the same thing ever time. The bike has drag pipes on it with no baffles in them.The plugs are black and is running rich because the exhaust is coming out with a hint of black. I have heard lots of different things that everyone thinks it but there is always something else that makes me think differently is there anything you can do to help me out?

Answer
the reason your bike is popping  and running rough is because it running two rich. First, if your bike was running fine and just started running rich its not the carb. There is nothing in the carb that will make it run more fuel in the bike. The jets do not get bigger with time. Now if you have made changes in the bike, like exhaust, cams ETC that is a different story.

I would look at the coil and OHMs test it. You said it runs fine for about 3-5 miles and then runs bad. the coil might be heating up and breaking down causing the plugs to foul.

Good luck and happy riding
Mike