FMF Factory 4.1 Slip On

2 replies to this topic
  • norm02

Posted November 26, 2012 - 07:10 PM


I just finished installing it and fired it up for the first time. Sounds awesome but it's a bit louder than I thought it would be. Not sure how much quiter it is with spark arrestor installed but will find out soon. Couldn't let it run long since the header started to glow. Will have more feedback on results once it has been re-jetted. Very easy to install and looks great!

Visit the ThumperTalk Store for the lowest prices on motorcycle / ATV parts and accessories - Guaranteed
  • norm02

Posted December 05, 2012 - 07:42 PM


Just got it back and rode it for the first time. Still love the looks and it sounds awesome. I haven't tried it with the spark arrestor in it yet but I'm assuming that it will quiet it down some.

  • throttle violence

Posted December 05, 2012 - 07:50 PM


i had the spark arrestor in my yz450 and took it out it made much more overrev pulled further in each gear its not that loud
you can hear it on utube yamaha yz450f power 2011 model


Join Our Community!

Even if you don't want to post, registered members get access to tools that make finding & following the good stuff easier.

If you enjoyed reading about "" here in the ThumperTalk archive, you'll LOVE our community. Come join ThumperTalk today!

The views and opinions expressed on this page are strictly those of the author, and have not been reviewed or approved by ThumperTalk.