How To Repack Insulation In A Two Stroke Dirt Bike Exhaust Muffler | Gain Two Horsepower | KTM 300

Recently I've been noticing how bad my exhaust sounds on my two-stroke KTM 300. The horrible exhaust note has developed slowly over time; until you compare it to a new bike, you probably wouldn't really notice. That has led me to this project where I will show you how to disassemble your exhaust muffler and repack the fiberglass insulation. It comes as a promise on the packaging of the new FMF insulation that you can get up to two horsepower back by doing this simple fix.
In my case, the insulation packing was just about as bad as it could get. I had recently had an oil seal that was leaking inside the engine. This caused the engine to burn oil which soaked into the fiberglass packing and completely saturated it. Over time the oil baked into the fiberglass making it one solid cake and rendering it virtually useless as insulation.
This of course caused the exhaust to sound terrible. After repacking the muffler I thought I would be able to feel some performance benefits. After all, I don't think it could have been much worse so if there was ever a time that you'd feel an improvement, this was it. As it would turn out, I really couldn't tell the difference other than the sound. Through the power range, the bike felt the same to me, however, you would have to be very sensitive to be able to feel a two-horsepower gain. That being said, the bike sounds like a proper two-stroke now which by itself is completely worth the cost and effort for this project.