So many possibilities…Is the pump running but not building pressure? Is the pump failing altogether? Is this only on highway, not around town (possible fuel starvation)? When it dies, do you hear fuel pump whine or is pump totally dead? If pump totally dies could be relay failure if relay is used in circuit. Excessive current draw could cause overheating of the pump. Verify all connections including all grounds. If the pump is running but not supplying fuel there are other possibilities. Pump should be installed as close to tank as possible otherwise you could develop vapor lock. If fuel tank is not venting properly could cause problem. I have seen bikes with stuck vent valves in gas cap more than once cause problems. After a few minutes of driving a vacuum would develop in gas tank and bike would fuel starve and stall. After sitting for a few minutes vacuum in tank would bleed off and bike would start only to do the same thing again. Figured it out when I noticed a hiss taking off the gas cap to see if I ran out of gas. Next time it stalled I popped off gas cap and she fired right up. New vented cap and no more issues. A cracked fuel hose between tank and pump could cause the pump to aerate. Also double check to make sure there are no issues in the tank, cracked pickup tube, etc. depending on how tank is set up. Main thing is to determine if pump is totally failing, if so check power and grounds. If pump is whining then check for vapor lock of pressure issue. As soon as it dies remove fuel hose from carb and crank engine to see if pump is pumping. A fuel gauge in the line to the carb is always a good idea for this exact reason. Always nice to verify fuel pressure at all times.
PS. Caspr49, always better to start a new thread of your own. You'll get more replies.