i've seen a fake one before...was driving behind this old pulsar.....the guy did a gd job...even made the muffler too....but it looks funny...just made of aluminum....and u can see the one on the right one blow smoke and vibrate when he drive...the left one just sitting there all clean and stuff, not even a hint of smoke residue on it at all...hahahaha even the inside of the pipe is still clean...look really stupid