The best description I have heard of the sound of a Track/Kick 1.6/16 without a muffler, is a "pissed-off bumblebee"
BUT - Just because your rig is "trail only", it's no excuse to run open pipes. Some people actually go out into the "wild country" to enjoy the peace and quiet - including me! Do all of us a favor, and put some kind of cheap muffler on it!