Originally Posted by bigbutterbean
Pictures didnt show up I dont think, but I will tell you this. It wont run good for long with a straight pipe. At first, it will seem like you have more torque and probably better speed. Eventually, what will happen is the open pipe will mess with the port timing. First you will lose power intermittently, as if your clutch is slipping or something. Eventually, you may lose power altogether. I'm just telling you the fact is that ported 2 strokes need back pressure to maintain proper timing.
they dont need back pressure for proper timing, timing is controlled by the ports in the jug and do no change unless you do port work. piston ported two strokes need back pressure to keep the motor from over scavenging the fuel charge from the cylinder.