FMF Factory 4.1 SL Slip-On Exhaust
FMF's Factory 4.1 SL slip-on muffler is guaranteed to produce more horsepower throughout the entire RPM range when compared to the stock muffler. Each Factory 4.1 SL muffler is constructed from only aerospace grade materials that meet the California company's exacting specifications.
- Massive power gains throughout the RPM range
- Significant weight savings when compared to the stock muffler
- Fabricated using the highest quality alloy grade materials
- Fits OEM or FMF headers
- Comes with all required mounting hardware and easy-to-follow installation instructions
- FMF 94 dB quiet insert available (sold separately)
- Made in the USA
|Color||Varies (make selection above)|
|Country of Origin||USA|
|Finish||Varies (make selection above)|
|Mid-Pipe||Varies (make selection above)|
|Muffler End Cap||Stainless Steel|
|USFS Approved Spark Arrestor||Varies (make selection above)|
Fitment is guaranteed or your money back plus free return shipping.
Don’t waste time installing a product that doesn't fit. We worked hard ensuring that this product is an exact fit on the vehicles listed below.
- CRF150R 2007-2009, 2013-2019
- Raptor 700R 2006-2023
- WR250F 2007-2013
- WR450F 2007-2011
- YFZ450 ATV 2004-2009, 2012-2013
- YZ250F 4-Stroke 2006-2010
- YZ450F 2006-2009
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