tonight i was bord and opened up my exhaust pipe just to check it out. Its the short vance and hines pipe, 3 screws lets the muffler part slide out. Anyways it was wrapped with black crap on the inside. I think at one point the black crap (kind of like cotton) was white or a different color. I have heard about repacking exhaust pipes and I guess that thats what the stuff is? Anyways does that affect my performance at all since its all old and black? or can I just leave that old stuff in there? I dont want it to get quieter though.

 

that black crap isnt cotton its fiberglass however i dont know what kind of fiberglass it is i could easily tell you to go to home depot and buy some fiberglass insulation cuz it looks very similar but then that would be irresponsible of me cuz ive never repacked a muffler in my life but, its fiberglass if you want to try home depot then go ahead but if you do try to get some high temp. stuff good luck

 

Go to any dealership with a parts department and get some packing for the dirtbikes. Its the same stuff. I think FMF puts out a line of packing. Or just search the internet for packing.

 

Alright I got the stuff today and I wrapped it around real tight, tied it with wire and put it back in...sounds the same, and I think it may have given me some more low end power some how i dont know how but it feels like it...I got the stuff specifically made for repacking exhausts. I wasnt sure though which side faces what....there was a fluffy side and a kind of hard flat side. I put the kind of hard flat side touching the baffle, and rapped around that way...so that the fluffy part is on the outside (in the pipe but facing out...you know what i mean)...anyways...is this the correct way or should it be switched around?

 

I think you got it right, any increase in low end torque comes from backpressure. And the fluffy side being out definately would add backpressure. How's the top end? if its the same, you done good. If weaker try flipping it around. It's the scientific method yeah!