FMF Powercore 4 Slip-On Muffler for the Yamaha XT250

The FMF Powercore 4 Slip-On Muffler (044448) is an aluminum and stainless steel exhaust upgrade engineered for the Yamaha XT250 dual-sport platform. The factory XT250 exhaust is a heavy, stamped-steel unit weighing nearly 9 lbs with restrictive internal baffles and an integrated chamber that restricts exhaust velocity and traps thermal energy against the rear shock and airbox.

Constructed in the USA, the Powercore 4 utilizes an extruded aircraft-grade aluminum canister with a champagne-anodized finish paired with a stainless steel mid-pipe and Hi-Flo conical end cap. Internally, a straight-through perforated core wrapped in high-temperature packing reduces backpressure to improve low-end torque and mid-range throttle response on the air-cooled 249cc SOHC single. Weighing just 3.8 lbs (1.72 kg), it sheds approximately 5 lbs of high-mounted mass from the XT250 subframe. The muffler includes a removable US Forest Service (USFS) approved screen spark arrestor, maintaining legality on regulated public trails and backcountry BLM land.

Features:

• Substantial Mass Reduction: Weighs 3.8 lbs (1.72 kg), shedding approximately 5 lbs compared to the OEM stamped-steel muffler.

• Straight-Through Core Architecture: Perforated inner core reduces exhaust restriction to enhance low-end roll-on torque and midrange throttle response.

• Aircraft-Grade Aluminum Sleeve: Extruded aluminum canister with a durable champagne-anodized coating that resists roost abrasion and corrosion.

• Stainless Steel Mid-Pipe & Hi-Flo End Cap: Hand-welded stainless steel construction withstands chassis flex and continuous single-cylinder engine pulses.

• USFS-Approved Spark Arrestor: Ships with an internal stainless mesh spark arrestor certified for US Forestry trail compliance.

• Fully Serviceable & Repackable: Modular end-cap fastening allows routine repacking with FMF 4-stroke packing kits to maintain sound dampening and power output.

• Made in the USA: Engineered, manufactured, and assembled at FMF headquarters in Rancho Dominguez, California.

What's in the Box:

• 1x FMF Powercore 4 Slip-On Muffler with Stainless Mid-Pipe (Part #044448)

• 1x Pre-Installed USFS-Approved Screen Spark Arrestor

• 1x Stainless Steel Mid-Pipe Band Clamp

• 1x Subframe Mounting Hardware Kit

• 1x Installation Instructions Sheet

Fitment:

• 2008–2026 – Yamaha XT250

Fitment Notes:

• Carbureted Models (2008–2012): Direct bolt-on. Re-jetting or pilot screw adjustment is recommended to prevent lean conditions and deceleration popping.

• Fuel-Injected Models (2013–2026+): Direct bolt-on. The factory oxygen sensor is mounted in the OEM front header pipe and remains untouched.

• Header Compatibility: Slips directly onto the OEM Yamaha head pipe. Also compatible with aftermarket FMF Powerbomb and Megabomb head pipes designed for the XT250.

• Sound Tuning: Meets USFS requirements out of the box. Compatible with FMF’s optional 96dB / 94dB quiet insert (sold separately) for additional decibel reduction in sound-sensitive areas.

Part Number: 044448