What is the difference between the different exhaust models you might ask? Mike of HMF explains it this way:

• "The Sport Series is a great all around performance pipe.  It will produce the broadest power band across the RPM range. 102-104 dbs
• The Ballance Pro is the Bill Balance signature pipe that uses a torque range modifier insert to increase bottom and mid range torque.  Dbs same as above.  This is a great "woods" pipe.
• The QRS or "Quiet Race Series" is a great pipe that uses a mechanical core to bring sound levels down from the pipes above while still flowing well enough to produce big gains.   Around 100dbs depending on the model. 
• The Quiet core insert will work with the sport as well as the Ballance with TRM removed.  It will NOT work with the QRS.  Quiet core will bring db levels down by 4-6
• Which pipe you choose will depend on where and what type of riding you do. 
  As far as tone is concerned, HMF is probably the deepest sounding ATV and Dirt bike silencer out there. . .IMO
  HMF Optimizer Fuel Controller Recommended" 

You can purchase the HMF exhaust at: https://hmfengineering.com/shop.php?category_id=4263

If you would like more information, or you would like ot discuss the new exhaust systems for the 700xx you can join our community free! http://trx700xx.net/forum/index.php?topic=57.15