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FMF Q4 S/A Silencer
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FMF Q4 S/A Silencer

Our price: $260.96$341.99

MSRP: $319.99 - $379.99 - You save up to $59.03 (18% off)

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    -Dan Thomas, CEO and Founder

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    The FMF Q4 S/A Silencer, perfect when you need exceptionally quiet performance. You’ll feel the power. You just won’t hear it.

    Low sound output is the name of the game with the Q4. 96dB or under to be precise, with most models coming in below 93dB. Plenty of room for you to get into the most restrictive trails and tracks. You can thank the system of chambers, baffles, and packing material for that wonderful sound of silence. It’s not just quiet though, the S/A model sports a removable USFS approved spark arrestor that won’t clog or burn through. Best of all, you still get that signature FMF boost in power to keep you happy.

    So don’t let sound restrictions stop you from wringing out the throttle. Put an FMF Q4 S/A Silencer on your ATV or dirt bike for some quiet, spark arrested goodness.

  • Max 96dB sound output with most models 93dB or less
  • USFS approved spark arrestor with no screen to burn through or get clogged
  • Increased packing material volume
  • Great power gains along with lower sound output
  • Fits with FMF or stock head pipes
  • Removable spark arrestor
  • Aluminum alloy and stainless steel construction
  • Proprietary series of baffles, chambers, and multistage packing material

FMF Q4 S/A Silencer Reviews

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0 of 0 people found this review helpful.

Great Tone

Comments On Aug 07, 2015:Bought it for a 2006 dual pipe crf250r. Very quiet bike for a 250. The fmf pipe came with detailed instructions as well as all the parts needed and a few stickers. Because it went on a relatively quiet bike the pipe didn't quiet it down a whole bunch but the tone is great. A bit more low end, great pipe if you want a good sound and a little power without making it super loud like a powercore.

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Good but a tight fit.

Comments On Jul 28, 2015:First of all, I paired this up with the FMF Power Bomb exhaust header pipe. This system gets rid of the factory clamp for my bike, so it is a "direct fit" that holds it into place. I had troubles getting the two pipes to seed together perfectly. After about 45 minutes of mounting and un-mounting the pipes and spraying wd-40 at the contact points they finally slipped on and mounted up. Also, the muffler did contact my rear fender so I had to cut some of that away. Also, the FMF customer service line was extremely helpful. All in all it sounds mean, not necessarily louder, just meaner. I am satisfied with this product and Rocky Mountain delivered on time, with the cheapest price ($70) cheaper than anywhere else.

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Comments On Jul 19, 2015:Great sound and easy install...

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0 of 1 people found this review helpful.

Easy install

Comments On Jul 06, 2015:Nice sound and easy to install.

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1 of 1 people found this review helpful.

Good pipe, fit perfect

Comments On Mar 30, 2015:The FMF Q is a big improvement over stock; it's quieter and provides better low-mid hit. The Q is quite a bit longer than stock so the bike has a different look, but the pipe is a nice addition. I'm rating the pipe with a 4 because I was expecting / hoping it'd be more quiet than it is - that being said it is more quiet than stock and has a better overall sound (deeper). I was also expecting a bigger power gain than I felt. All the threads on 2008-2009 YZ450F's say that any aftermarket pipe will add 5 horses, I'm not sure the Q gives that much of a boost. With the Q and a 165 main jet I was better able to wheelie through the deep sandy whoops (4th gear). I also have some peace of mind knowing my pipe is now compliant to state and federal laws regarding noise and spark arrests. Install was easy, I didn't need either of the 2 inserts it came with. The Q simply fit over my header. I used high temp silicon (gasket maker would also work) to seal the 2 pipes together (as listed in the instructions). Install was 15 min. including the time finding my silicon.

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Slip on fmf q4

Comments On Jan 26, 2015:I bought the exhaust to bolt up to my fmf power bomb header and it was a great fit no leaks and loved the tone very mild but no power restriction and fast shipping from Rocky Mountain

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Comments On Dec 03, 2014:This thing is HUGE! From the mounting bolt to the tip of silencer it is 1-3/4 inches longer and weights over a pound more than the stock silencer. If you are looking for performance enhancer I would go with the titanium power core. It has a spark arrester available separately. If all you care about is sound then the Q4 is the one for you.

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Another score for FMF!

Comments On Dec 07, 2014:Great exhaust, I love how loud it is though I've had louder. It really adds the extra umph to the wheeler, Hotcams, the Q4 and a Wiesco high comp piston with this wheeler really turns it into an unstoppable force of nature.

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FMF Silencer

Comments On Jan 10, 2014:The silencer makes good power and meet a 98 dec sound test.

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1 of 1 people found this review helpful.

Huge power gains!

Comments On Dec 31, 2013:I have this silencer on my 2013 RMZ450 and my 2009 RMZ450 and it is amazing. I pair it with a power-bomb head pipe and I notice big HP gains from bottom to top end. I believe it is much more quiet then stock but has a better sound. Two thumbs up FMF I would definitely recommend. My only complaint is that the sticker has started to peel off but I stuck it back down with heat resistant epoxy and it looks as good as new!

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