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FMF

FMF Factory 4.1 RCT Full System Exhaust

Name: FMF Factory 4.1 RCT Full System Exhaust
Brand: FMF
SKU: 41639
Price: 809.99 USD
Availability: OutOfStock

$899.99 $809.99 Save $90.00

SKU: 41639

Out of Stock

Free Shipping over $200

$100 Minimum Order

Non-Returnable Item

DIY PRO SHOP

Moderate — 2–4 hours

Overview

The FMF Factory 4.1 RCT full system is a high-performance exhaust designed to improve your motorcycle's power band, reduce weight, and enhance looks. Constructed from aerospace-grade materials and manufactured in Southern California, this system features the patented MegaBomb header design. This design allows exhaust gases to expand and cool before ramping back up at a higher velocity, resulting in improved torque and over-rev.

The muffler is shorter than OEM, making it less susceptible to damage and helping to centralize mass by moving it closer to the motor. The rear end cap is engineered for quick tuning, with a retaining ring to hold inserts securely. This exhaust system offers massive power gains throughout the RPM range and significant weight savings over the stock exhaust. It includes a removable spark arrestor and meets AMA and FIM sound requirements.

Show original supplier description

The FMF Factory 4.1 RCT full system is a high-performance exhaust designed to improve your motorcycle's power band, reduce weight, and enhance looks. Constructed from aerospace-grade materials and manufactured in Southern California, this system features the patented MegaBomb header design. This design allows exhaust gases to expand and cool before ramping back up at a higher velocity, resulting in improved torque and over-rev. The muffler is shorter than OEM, making it less susceptible to damage and helping to centralize mass by moving it closer to the motor. The rear end cap is engineered for quick tuning, with a retaining ring to hold inserts securely. This exhaust system offers massive power gains throughout the RPM range and significant weight savings over the stock exhaust. It includes a removable spark arrestor and meets AMA and FIM sound requirements.

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

Brand	FMF
Part Number	41639
Category	Exhaust

Videos

Dirt Bike Tech Tips/How-To: Install a Muffler | FMF Factory 4.1 RCT

Installing a FMF 4.1 Factory Slip-On | Dennis Kirk Tech Tip

Before You Buy an FMF Exhaust - Check This Out!

2021 YZ250F FMF 4.1 INSTALL *FULL SYSTEM*

FMF Factory 4.1 Exhaust Review - AMX Product Insights with Riana Crehan

FMF Factory 4.1 Full Exhaust System Install | Motorcycle Superstore

FMF 4-Stroke Spark Arrestor Insert Tech Tip

2020 HONDA CRF110 FMF FACTORY 4.1 TITANIUM EXHAUST INSTALL!!!!!!

FMF 4.1 RCT Exhaust Installation + WEIGHT & SOUND COMPARISON VS STOCK -- 2017 KTM 500 EXC-f

FMF Factory 4.1 Titanium Anodized Slip On Muffler With Carbon Cap | Review

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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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