If you want the performance of the HMF Exhaust System, without the noise...order the Quiet Core Insert! Adding an HMF Exhaust System to your utility ATV is one of the best ways to add bolt-on power. However, no argument...it's LOUD! Springing a little extra for this HMF Quiet Core Insert will lower the decibel level to UNDER the noise ordinance level in your area.

Since many riders enjoy public land that is policed by agencies such as the USFS, it's a good idea to obey these ordinances. You can do this by installing this HMF Quiet Core. Most importantly...according to HMF, you will retain 95% or more of the power the pipe gave your quad in the first place. SO...which is more important? 5% of the power...or 100% of the riding opportunities? 

• We recommend re-jetting the exhaust whenever a Quiet Core is installed. Failure to do so can lead to several problems and can damage the exhaust and void the warranty.
• The Quiet Core will not work with the HMF Ecosystem or Quiet Race Series Exhaust because those models have mechanical cores with no room to fit the Quiet Core into the exhaust.
• You cannot use the Torque Range Modifier with a Quiet Core at the same time, only one can occupy the Exhaust space