Home » FMF 4.1 RCT Stainless Slip-On - Kawasaki KX450 / X / SR (2019-2023)
FMF 4.1 RCT Stainless Slip-On Kawasaki KX450 / X / SR (2019-2023)
FMF Racing

FMF 4.1 RCT Stainless Slip-On - Kawasaki KX450 / X / SR (2019-2023)

SKU: FMF042369
No reviews
In stock
$599.99
Product details
  • Type Exhaust
  • MPN 042369
Compatible Models +
Make & Model Year Range
KAWASAKI KX450F 2019 - 2023
KAWASAKI KX450X 2021 - 2023
KAWASAKI KX450SR 2022 - 2023

Overview

The FMF Factory 4.1 RCT Stainless Slip-On is built to elevate your Kawasaki KX 450, X, or SR (2019–2023) with noticeable power gains, weight savings, and track-ready tuning features. With FMF’s Resonance Chamber Technology™ and Factory Forward Engineering, it delivers pro-level throttle response and a centralized mass layout to sharpen handling where it counts.

Key Features

  • Proven Power Gains: Boosts horsepower and torque across the entire RPM range.
  • RTS Tuning System: Rapid Tuning System makes trackside insert swaps fast and easy.
  • Crash-Resistant Profile: Compact muffler design reduces vulnerability in the event of a tip-over.
  • Lightweight Build: Weighs just 7.3 lbs—lighter than stock despite stainless steel midpipe.
  • Flexible Fitment: Compatible with FMF or OEM headers.
  • Built in the USA: 100% constructed at FMF’s Southern California factory.

Specifications

  • Fitment: Kawasaki KX 450 / X / SR (2019–2023)
  • Item ID: 042369
  • Type: Slip-On
  • Construction: Aluminum canister with stainless steel midpipe
  • Finish: Natural
  • End Cap: Carbon fiber
  • Spark Arrestor: Screen insert included
  • Quiet Insert: 94 dB insert included
  • Weight: 7.3 lbs.
  • Use: Closed Course Only

Take your KX to the next level with FMF’s stainless 4.1 RCT—where durability meets factory-built performance.

Shipping Information

We strive to get your order to you as quickly as possible! Here’s what you need to know about our shipping policies:

Fast Shipping: Most items ship within the same day or within 48 hours of your order being placed.

Custom Orders: Please allow additional processing time for custom or made-to-order products.

Flat Rate Shipping: Enjoy $9 Flat Rate Shipping on all standard orders.

Free Shipping:

Orders over $90 qualify for FREE shipping!

Always FREE shipping on:

  • ASV Levers
  • Rough Country Products
  • S3 Power Sports Products

No Sales Tax Outside Minnesota: Since we only have a tax nexus in Minnesota, sales tax is only collected on orders shipped within MN.

Customers with shipping addresses outside Minnesota automatically save on sales tax—just one more way to get great value!

(Please consult your local tax policies for compliance in your area.)

We’re committed to delivering your products efficiently and reliably. Thank you for choosing us!

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