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Exhaust› Mufflers and Resonators

FMF

Powercore 4 HEX Muffler

$399.99 $359.99 Save $40.00

SKU: 042387

In Stock
In Stock
Ships by Sep 12
Free Shipping over $200
$100 Minimum Order
30 Days Return
INSTALL DIFFICULTY
DIY PRO SHOP

Moderate — 2–4 hours

Overview

The FMF Powercore 4 HEX muffler is designed to deliver race-inspired performance at an economical price. It features a durable construction with stainless steel and aluminum components, along with Space Age internal packing material for longevity. The internal core uses Hi-Flo technology and enhanced sonic evacuation for higher flow and increased power. A removable spark arrestor is included, and a quiet insert is sold separately.
Show original supplier description
The FMF Powercore 4 HEX muffler is engineered to provide race-inspired performance and rugged durability without a premium price tag. Drawing inspiration from FMF's top-tier products, this muffler aims to deliver an overall increase in power and torque. The internal core is designed with Hi-Flo technology and enhanced sonic evacuation to achieve higher flow rates and boost overall power output. This slip-on muffler features a single configuration and a natural aluminum finish, with a stainless steel midpipe and endcap. It comes with a removable screen insert spark arrestor, and a quiet insert is available for separate purchase. The FMF Powercore 4 HEX has a listed weight of 6.4 lbs. This product is intended for closed-course competition use only and is not designed or intended for use on public roads or land. Such use is prohibited by Federal and State regulations. Users will need to complete a form acknowledging this racing-only purpose before purchase. It is specifically designed to fit the 2020-2021 Kawasaki KLX300R. Compatibility with specific headers should be verified by checking the fitment tab.

Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.

Fitment

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Specifications

BrandFMF
Part Number042387
CategoryExhaust

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Returns & Fitment

Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

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Shipping

Orders are processed in 1–3 business days. In stock parts ship promptly from our partner network. Special-order items either aren’t currently stocked or are built to your spec — expect 4–6 weeks. If a part goes on backorder while your order is in the queue, we’ll reach out and work through discounted alternatives together.

Free shipping over $200 in the continental US. Alaska, Hawaii, U.S. territories (Puerto Rico, U.S. Virgin Islands, Guam, American Samoa, and the Northern Mariana Islands), and international orders carry surcharges — most appear at checkout. Some exceptions (LTL freight, or suppliers who quote freight only after we place the order) won’t. In those cases we’ll reach out with the exact charge before your order moves forward.

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