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FMF

FMF Factory 4.1 RCT Exhaust System Yamaha YZ450F / YZ450FX / WR450F 2014-2018

Item: P291611
5 Read 5 Reviews 18 Q&As Write a Review

The FMF Factory 4.1 RCT full system is constructed from aerospace-grade materials that meet FMF's exacting specifications and is 100% manufactured in … Read More

$719.99$989.99
$799.99$1,099.99
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Product Details

This product is legal in California only for racing vehicles which may never be used, registered or licensed for use upon a highway.

FMF Factory 4.1 RCT Full Exhaust Yamaha YZ450F / YZ450FX / WR450F

The FMF Factory 4.1 RCT full system is constructed from aerospace-grade materials that meet FMF's exacting specifications and is 100% manufactured in their Southern California factory. The patented MegaBomb header design allows exhaust gases to expand, cool and ramp back up at a higher velocity. This results in torque gains typically associated with longer headers, and the healthy over-rev of a short header. The muffler itself is shorter than OEM mufflers, making it less susceptible to crash damage and complements the centralized mass design by moving it closer to the motor. The rear end cap was engineered for fast and easy tuning by utilizing a retaining ring to keep the standard and optional inserts in place.

Features:

  • Massive power gains throughout the RPM range
  • Huge weight savings over stock exhaust
  • RTS (Rapid Tuning System) for quick and easy track-side tuning
  • Removable spark arrestor included
  • MegaBomb Header
  • Quiet insert sold separately
  • Meets AMA and FIM sound requirements 
  • 100% made in the USA

Weight:

  • Stainless Steel / Aluminum / Carbon end cap 7.5 lbs
  • Titanium / Titanium / Carbon end cap 5.7 lbs
Made in the USA
Product Style RevZilla Item # Store Sku MFR. Product # Availability
Product Style Titanium/Blue Titanium/Carbon Fiber RevZilla Item #1001591 Store Sku MFR. Product #44412/044412 AvailabilityCloseout: This product is no longer available
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This product is vehicle specific.
Select a vehicle to ensure fitment.
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FMF Factory 4.1 RCT Exhaust System Yamaha YZ450F / YZ450FX / WR450F 2014-2018 Resources

Product Description
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Resources
5 Customer Reviews
5 5/5
18 Questions & 3 Answers
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