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Exhaust› Mufflers and Resonators

FMF

Factory 4.1 RCT Muffler

$599.99 $539.99 Save $60.00

SKU: 041517

In Stock
In Stock
Ships by Sep 13
Free Shipping over $200
$100 Minimum Order
30 Days Return
INSTALL DIFFICULTY
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Easy — 1–2 hours

Overview

The FMF Factory 4.1 RCT Muffler is a high-performance slip-on exhaust system designed for dirt bikes. It incorporates FMF's Resonance Chamber Technology for improved performance. Constructed with aerospace-grade materials, it features a stainless steel midpipe and a natural aluminum canister with a carbon end cap.
Show original supplier description
The FMF Factory 4.1 RCT Muffler is engineered to deliver significant performance enhancements to your dirt bike. It utilizes FMF's advanced Resonance Chamber Technology, both internally and externally, to optimize exhaust flow and sound. Constructed from aerospace-grade materials meeting exacting specifications, this slip-on muffler features a durable stainless steel midpipe and a natural aluminum canister, capped with a carbon fiber end cap. It comes with a screen-type spark arrestor, essential for off-road riding, and meets AMA professional sound requirements. The FMF Factory 4.1 RCT is noted for providing massive power gains throughout the entire RPM range and offers substantial weight savings compared to stock systems. This FMF muffler can be used with either an FMF header or the stock OEM header, offering flexibility in customization. It is important to note that this product is intended "For Closed Course Competition Use Only" and is "Not Intended for Street Use." Included with the muffler are the stainless steel mid-pipe, the muffler itself, a spark arrestor, a spark arrestor ring, a muffler washing plug, and instructions. The unit has a listed weight of approximately 5 lbs.

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 Number041517
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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