FMF Factory 4.1 Anodized Titanium Exhaust Review

Reviews  |  26 September 2017

FMF Factory 4.1 Anodized Titanium Exhaust Review main image

One of the more costly replacements on your dirt bike, an aftermarket exhaust system can offer huge benefits to any rider, whether they're chasing more power, more acceleration, less weight or simply better looks. FMF is far and away the #1 brand when it comes to replacing your dirt bike exhaust, and whether you have a 2 stroke or a 4 stroke they've got you covered. When we got out hands on our 2017 Honda CRF450R Project Bike, the exhaust was one of the first things we looked at upgrading, and with some help from our friends at FMF, it wasn't long before we had an FMF Factory 4.1 Dual Anodized Titanium Exhaust System ready to roll.

The Factory 4.1 system is made up of two separate pieces, the dual anodized titanium slip-on mufflers, and the titanium Megabomb head pipe. So let's start with the dual mufflers. 

FMF Factory 4.1 Anodized Titanium Mufflers

There's an almost endless amount of technology and aerospace grade materials and features that come together in the form of the anodized titanium mufflers, but the benefits of the mufflers are fairly straightforward, so let's run through them now.

  • Power gains - will vary amongst different makes and models of dirt bikes, but the Factory 4.1 mufflers offer massive power gains throughout the entire RPM range. Bottom end power in particular is noticeably increased with the addition of a Factory 4.1 system.
  • Weight savings - the titanium mufflers offer huge weight savings over your stock exhaust, no matter what dirt bike you have. When it comes to going fast, dropping unnecessary weight is absolutely key.
  • Smoother power delivery - one of the key features of a premium aftermarket exhaust, the FMF Factory 4.1 offers a far smoother power delivery when you twist the throttle wide open.
  • Ready to race - this thing is ready to race straight out of the box.
  • Factory forward engineering - the FMF system is specifically designed to move the mufflers closer to the motor, centralizing mass and creating a far more rideable dirt bike.
  • Looks - the anodized titanium mufflers are easily the most attractive exhausts on the market. The iconic FMF logo pops against the anodized blue of the mufflers, and the carbon fibre end caps are a thing of beauty.
  • Sound - you haven't heard a 4 stroke roar until you've heard it from the back of an FMF Factory 4.1 muffler. Crisp, clean and powerful, no other sound comes close.



"The FMF took the power of the CRF450R to a whole new level. Shooting our Range Release films this year, the FMF made a huge difference. Bottom end acceleration increased massively, and a more consistent spread of power throughout the whole RPM range was definitely noticeable. Plus, the thing looks and sounds amazing" - Jake Lowe, resident MXstore superstar. 


FMF Megabomb Titanium Header Pipe

Leading the field in technogical advances when it comes to dirt bike header pipes, the FMF Megabomb truly is a work of art. You can bolt on a Megabomb with an existing FMF Factory 4.1 slip on for as much as a 3hp boost, and those kind of gains give you a huge advantage over the competition. Let's have a run through the main benefits of the Megabomb.

  • Power gains - Megabomb technology revolves specifically around  low end to mid range power gains, increasing your acceleration and power off the mark and out of corners significantly. The Megabomb also broadens the mid to top end power gains over the stock header.
  • Weight savings - as with the mufflers, the lightweight titanium construction offers a much lighter header option compared to stock.
  • Looks - the titanium construction not only offers a super lightweight piece of technology, but makes these things look stylish as hell.


While some people might think installing an aftermarket exhaust could be a complicated process, it's really one of the easiest parts to remove and install on your dirt bike. Check out our How-To Exhaust Installation Guide and see how simple it is to chuck one of these beauties on your prized machine.


The Verdict

They may be on the upper end of the price spectrum when it comes to aftermarket dirt bike parts, but an FMF Factory 4.1 Anodized Titanium Exhaust System is worth every cent. The power gains from a straight-from-the-box part are simply unmatched, and you'll hardly believe how much faster you can blow out of a tight corner with one of these versus your stock exhaust. If you're serious about your racing and are looking to maximise every part of your dirt bike to its full potential, you'd be crazy to look anywhere else when it comes to an exhaust system. We guarantee you will not be disappointed!


Check out the best of the FMF Exhaust range via the links below:

Comments (1)

Would love one

I'm very seriously considering buying one for my bike as they look awesome and increase the power but don't quite have the money

28 September 2017

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