Product Details
FMF Q4 HEX S/A Slip-On Exhaust Yamaha YZ450F / FX / WR450F
Loud pipes might save lives on the street but in the dirt sound is the number one killer of riding trails and regulated track hours. If you have been searching for a performance enhancing muffler that does not wake the dead, then the FMF Q4 HEX is the muffler for you. FMF approached the design process of the Q4 HEX with the goal of achieving more power, while keeping noise levels to a minimum. After countless hours of testing, FMF proved you don't have to settle for a plugged up, horsepower-robbing moto muffler to remain sound compliant.
Features:
- Less sound equals more ground (helps keep our riding areas open)
- Meets USFS and FIM World Enduro sound regulations
- Power gains throughout the entire RPM range
- Spark arrestor included
- Pounds lighter than stock
- Rugged design for off-road endurance
- Only US manufacturer to offer dedicated quiet exhaust systems
- Can be used with stock or FMF Header
- Weight: 6.1 lbs
- 100% Made in the USA
Note: Image is for reference only. Actual slip-on muffler / mid-pipe will vary.

Product Style | RevZilla Item # | Store Sku | MFR. Product # | Availability |
---|---|---|---|---|
Product Style Stainless Steel/Aluminum/Stainless Steel | RevZilla Item #1298183 | Store Sku | MFR. Product #044442 | AvailabilityIn Stock: Ships within 24 hours |
- Yamaha
- WR450F 2019
- YZ450F 2018-2025
- YZ450F 50th Anniversary Edition 2024
- YZ450F Monster Energy Race Edition 2022, 2023, 2024, 2025
- YZ450FX 2019-2026
- Beta
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- 350 RR Race 2025
- 350 RR Race Edition 2021-2025
- 350 RR X-Pro 2025
- 390 RR 2023-2025
- 390 RR Race 2025
- 390 RR Race Edition 2020-2025
- 390 RR X-Pro 2025
- 430 RR 2023-2025
- 430 RR Race 2025
- 430 RR Race Edition 2020-2025
- 430 RR X-Pro 2025
- 480 RR 2023-2025
- 480 RR Race 2025
- 480 RR Race Edition 2020-2025
- 480 RR X-Pro 2025
- Gas Gas
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- EX 350F 2021-2023
- EX 450F 2021-2023
- MC 250F 2021-2023
- MC 350F 2022-2023
- MC 450F 2021-2023
- Husqvarna
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- FC250 2019-2022
- FC350 2016-2017
- FC350 2019-2022
- FC450 2016-2017
- FC450 2019-2022
- FC450 Rockstar Edition 2018-2021
- FE250 2017-2019
- FE250 2020
- FE250 2014-2016
- FE350 2017-2019
- FE350 2020-2022
- FE350 2014-2016
- FE450 2017-2019
- FE450 2023
- FE450 2015-2016
- FE501 2017-2019
- FE501 2020-2022
- FS450 2021-2022
- FX350 2017-2018
- FX350 2019-2022
- FX450 2017-2018
- FX450 2019-2022
- KTM
- 250 SX-F 2016-2018
- 250 SX-F 2009-2015
- 250 SX-F Factory Edition 2015-2017
- 250 XC-F 2016-2018
- 250 XC-F 2019-2022
- 250 XC-F 2009-2015
- 250 XCF-W 2009-2016
- 350 EXC-F 2017
- 350 SX-F 2016-2018
- 350 SX-F 2019-2022
- 350 SX-F 2011-2015
- 350 XC-F 2016-2018
- 350 XC-F 2019-2022
- 350 XC-F 2011-2015
- 350 XC-F Kailub Russell 2021
- 350 XCF-W 2020-2022
- 350 XCF-W 2012-2016
- 400 XC-W 2009-2010
- 450 EXC 2009-2011
- 450 EXC-R 2008
- 450 SMR 2021-2022
- 450 SMR 2013
- 450 SX-F 2016-2018
- 450 SX-F 2019-2022
- 450 SX-F 2007-2015
- 450 SX-F Factory Edition 2015-2017
- 450 SX-F Factory Edition 2018-2021
- 450 SX-F Factory Edition 2012-2014
- 450 XC-F 2016-2017
- 450 XC-F 2019-2022
- 450 XC-F 2009-2015
- 450 XCF-W 2023
- 450 XCR-W 2008
- 450 XC-W 2009-2016
- 450 XC-W Six Days 2010-2011
- 500 XCF-W 2020-2022
- 500 XCF-W 2012-2014
- 500 XC-W 2013-2016
- 505 SX-F 2008
- 505 XC-F 2008-2009
- 530 EXC 2009-2011
- 530 EXC-R 2008
- 530 XCR-W 2008
- 530 XC-W 2009-2010
- Kawasaki
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- KX250 2021-2024
- KX250 2025-2026
- KX250X 2021-2024
- KX250X 2025-2026
- KX450 2024-2026
- KX450 2019-2023
- KX450 50th Anniversary Edition 2024
- KX450SR 2022-2026
- KX450X 2021-2023
- Triumph
- TF450C 2026
- TF450E 2026
- TF450RC Edition 2025
- Yamaha
- WR250F 2021-2023
- WR250F 2015-2019
- YZ250F 2014-2018
- YZ250F 2019-2026
- YZ250F 70th Anniversary Edition 2026
- YZ250F Monster Energy Race Edition 2022-2023
- YZ250FX 2015-2019
- YZ250FX 2020-2025
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