Big Gun Eco Series Slip On Exhaust for 1999-2014 Honda TRX400EX / X 07-1122

The Big Gun 07-1122 ECO Series Slip-On Exhaust is a budget-friendly performance upgrade specifically designed for Honda’s 400cc sport ATV line. It is a direct "slip-on" replacement for the factory muffler.

Fitment

This exhaust is confirmed to fit the following models:

• Honda TRX400EX Sportrax: 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008

• Honda TRX400X: 2009, 2012, 2013, 2014

Specifications

The Big Gun 07-1122 ECO Series is constructed with a focus on durability and weight savings compared to the heavy stock system.

• Materials: Built with 304 stainless steel mid-pipe tubing and a 6061 brushed aluminum muffler canister.

• Performance: Typically provides a 3–6 horsepower increase and improved throttle response.

• Sound & Safety: Produces a deep exhaust note (approx. 98dB) and includes a removable USFS-approved spark arrestor for trail legality.

• Design: Features a slip-fit mid-pipe that allows for sub-frame movement, preventing the exhaust brackets from snapping during hard landings or rough terrain.

• Critical Installation Note

  Since the TRX400EX/X is a carbureted machine, installing a higher-flowing exhaust like the Big Gun ECO Series will cause the engine to run "lean" (too much air, not enough fuel).

  To prevent engine overheating, backfiring on deceleration, or potential piston damage, you must re-jet the carburetor. This usually involves installing a larger main jet and adjusting the fuel mixture screw to account for the increased airflow.