4-STROKE POWER EXHAUST
  • Horsepower and torque gains upto 20%
  • CNC Bent 304 stainless steel header, midpipe and tail sections.
  • Stainless steel CNC machined header flanges
  • Custom designed. 100" wall aluminum extrusion muffler body.
  • Front/Rear end caps CNC machined from billet aluminum.
  • Muffler mounts CNC machined from billet aluminum.
  • Stainless muffler cores.
  • All mufflers completely rebuildable and repackable.
  • O-Ring seal at tail pipe to muffler joint.
  • All FAT BOY 4 exhaust systems are individually serial numbered.
HONDA 250X/300EX
HONDA 400EX
   
HONDA TRX 250EX
KAWASAKI KFX 400
   
SUZUKI LTZ 400
YAMAHA RAPTOR
   
YAMAHA WARRIOR
FAT BOY 4 TURNDOWN

or click here to view the Duncan Racing Website