By: Matt Sirevaag (AKA Vaaaaaaag)
You just took ownership of a new KX450 and you want to change the engine characteristic with a new exhaust. However when listening to Keefer rant on the Pulp MX Show about A-Ray giving away mufflers like he’s Oprah on a Christmas special has you hesitant. You may wonder why the aftermarket exhaust industry didn’t just do as Kawasaki did from the factory and use a rubber grommet to help with vibration and help yield breaking sub frames. Well for whatever reason most exhaust companies mufflers are solid mounted so sometimes consumers are breaking the tabs off the subframes thus mufflers are being laid all over local tracks like toys left on the floor by a three year old.
After breaking our muffler bracket on our KX450 test bike, we decided to take the stock rubber and mounting hardware to install the new aftermarket FMF exhaust. This is a simple mod that even the most novice mechanic can do at home. Take your aftermarket muffler and stick it in a soft vise or have your wife hold your muffler. Drill/hog out the existing mounting hole with 5/8 drill bit or step bit. Next, install the rubber grommet and hardware from your stock exhaust into your new muffler. Boom! Now you have aftermarket exhaust mounted the way Kawasaki intended it to be. You will get a small amount of float out of the rear section of the muffler, but we have not noticed any unnecessary vibration or slop when riding.
