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FMF Q4 Hex Spark Arrestor Slip-On Exhaust
FMF Q4 Hex Spark Arrestor Slip-On Exhaust

$341.99 - $431.99
10% Off - Save up to $48.00

Item #FMF002Z

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18 Reviews
4.8 out of 5 stars
5 Star   15 4 Star   3 3 Star   0 2 Star   0 1 Star   0
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All Reviews
Verified Purchaser Top 1000
Augusta Ga
Durability5/5Ease of Installation5/5Performance5/5Power4/5Style5/5
Quieter than stock

I got this for the spark arrestor for riding in places where required and to meet or beat the 96db threshold for certain hare scrambles/enduros. I was under the impression I could just bolt this on and not do any mapping changes to the efi on my 2013 RMZ 250...we'll it is true, though I did get a bog on a throttle blip one time before it was warmed up fully, again just once on the 1st trip out with it. This had never happened before.Hasn't happened since and I've had it out 3x since. So the verdict is still out on that but pretty sure it's good. I noticed a lot of low end gain but the same time I got the Q4 I went up two teeth on rear sprocket so can't attribute all of the extra grunt to the exhaust. With all that said I love the sound, perceived low end gain, and ability to ride and race places where I couldn't with out it.

Verified Purchaser
Placerville
Durability4/5Ease of Installation5/5Performance4/5Power4/5Style5/5
Good looking pipe, perfect fit

This installed very easy. It does not use the clamp in the center. The pipe is not real quiet, but not real loud. I wish it was quieter, but it is not bad. It is a good looking pipe, plus it takes care of my spark arrestor.

Top 250
Eugene, OR
Durability4/5Ease of Installation3/5Performance5/5Power5/5Style4/5
Greal Product and lighter then stock.

Nothing but praise for this. There are a few quirks to it though one of them being that it does not come fully assembled, so you need to be careful not to throw anything out by accident. By not fully assembled I'm talking about the spark arrestor insert. Coming to quirk number two they used an allen head instead of a 6mm/8mm so installing the insert is more of a pain then it should be. Quirk number three you will most likely need to by a hose clamp and install it where the pipe meets the muffler.

Verified Purchaser
Muskegon, Mi
Durability4/5Ease of Installation4/5Performance5/5Power5/5Style4/5
Perfect fit

I bought this for my 2012 rmz250 to ride in the trails and dunes and it fits perfect. The bike has more power and sounds great.

Verified Purchaser
Nevada City Ca
Durability5/5Ease of Installation5/5Performance5/5Power5/5Style5/5
FMF q4

Great exhaust with a good sound

Verified Purchaser
Michigan
Durability5/5Ease of Installation5/5Performance5/5Power5/5Style4/5
Awsome product!

I just bought a 2018 rmz250 and put this Q4 S.A. on it and it sounds great. It's a bit more quiet than the stock silencer and fits and looks great.

Verified Purchaser
Oregon
Durability5/5Ease of Installation5/5Performance5/5Power5/5Style4/5
FMF Q4

Easy to install. Make sure to save stock rubber grommets. They are required for the new install

Verified Purchaser
Durability4/5Ease of Installation5/5Performance4/5Power4/5Style4/5

Verified Purchaser
San jose ca
Durability5/5Ease of Installation5/5Performance5/5Power5/5Style5/5
Great pipe

Super easy to install. And even though its a quiet pipe. It sounds great. Much louder than stock. Power was night and day in difference

Michigan
Ease of Installation4/5Performance4/5Power4/5Style3/5
Pretty good

I have 2 small annoyances with this product
1. The muffler sticks out much farther than stock and contacts my plastics. Nothing has melted yet though
2. My stock clamp is too large for this pipe. I didn't buy my bike new so it is possible that it wasn't a stock clamp but I doubt it.
Other than that, it's a nice piece, looks well made, quieter than stock.

See 8 More Reviews
15 Questions
Answered:   11
Not Yet:   4
Hophead
Q: Has anyone put this on the 2019 Honda crf450?
1 month 16 days ago
DaveGearhead
Top 1
1 month 16 days ago
A: This muffler is not tied to that particular fitment. No idea if someone went against better judgement and tried it on their own.
Jayz
Q: Does this fit on the new CRF 150L here in Philippines?
3 months 2 days ago
robert
Top 10
3 months 2 days ago
A: This exhaust will not fit a crf 150l.
BradenH54
Q: So the spark arrestor is already built into the pipe itself? 
3 months 20 days ago
Michael
Top 10
3 months 20 days ago
A: It does come already installed, that is correct. You will still be able to remove and replace if need be.
Curious
Q: Is this slip on stamped U.S.F.S. use?
3 months 22 days ago
Paul
Top 10
3 months 22 days ago
A: The FMF Q4 Hex Spark Arrestor Slip-On Exhaust Meets U.S.F.S. and FIM World Enduro sound regulations. FMF includes a sticker which shows that the muffler meets the U.S.F.S. requirement, which you may apply to the muffler, or not.
SethBlanchard
Q: I have a 2018 YZ250F and the stock clamp is too big for the slip on. Any help here?
1 year ago
Dalton
Q: EFI Programmer
2 years 3 months ago
If I install this with the Megabomb header, should I go and buy an EFI programmer, or reprogram the injectors? What EFI box do I need or what fuel map do I need to download?
Danno
Q: Could you please identify the difference between the "Q4 HEX" and standard "Q4"
2 years 3 months ago
whitey
Q: Is the slip on stamped FOR U.S.F.S. ?
2 years 5 months ago
fmf Q4 hex spark arrestor slip-on muffler
maxcrf250l
Q: Is the Q4 Street legal in the EU (Germany)?
Over 3 years ago
Or maybe a hint where/how to best check? Thanks
MotoSportExpert
MotoSport Staff Expert
Over 3 years ago
A: All products sold on MotoSport.com are for US models only. We unfortunately do not have product fitment for non-us models. Also any street legal products are designed for US emissions and laws.
Johnathon168
Q: I currently have the fmf PowerBomb header on my kx450f and it runs great with no adjustments. Would I have to change or do anything if Added this?
Over 4 years ago
MotoSportExpert
Expert MotoSport Staff
Over 4 years ago
A: Normally when installing a slip-on only minor jetting changes are needed, if any at all. If your bike is currently jetted properly you will likely not have to make any changes after installing this slip-on. I would recommend installing the exhaust and riding the bike to see how it is running then tuning your carburetor from there if necessary.
1 - 10 of 15
Fitment

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# Part Numbers
Product Variant Manufacturer Part #
FMF Q4 Hex Spark Arrestor Slip-On Exhaust N/A
FMF Q4 Hex Spark Arrestor Slip-On Exhaust 041568
FMF Q4 Hex Spark Arrestor Slip-On Exhaust 041570
FMF Q4 Hex Spark Arrestor Slip-On Exhaust 042341
FMF Q4 Hex Spark Arrestor Slip-On Exhaust 043363
FMF Q4 Hex Spark Arrestor Slip-On Exhaust 044442
FMF Q4 Hex Spark Arrestor Slip-On Exhaust 045442
FMF Q4 Hex Spark Arrestor Slip-On Exhaust 041486
FMF Q4 Hex Spark Arrestor Slip-On Exhaust 042296
FMF Q4 Hex Spark Arrestor Slip-On Exhaust 043325
FMF Q4 Hex Spark Arrestor Slip-On Exhaust 043345
FMF Q4 Hex Spark Arrestor Slip-On Exhaust 043326
FMF Q4 Hex Spark Arrestor Slip-On Exhaust 044387
FMF Q4 Hex Spark Arrestor Slip-On Exhaust 044426
FMF Q4 Hex Spark Arrestor Slip-On Exhaust 044388
FMF Q4 Hex Spark Arrestor Slip-On Exhaust 044413
FMF Q4 Hex Spark Arrestor Slip-On Exhaust 041516
FMF Q4 Hex Spark Arrestor Slip-On Exhaust 043338
FMF Q4 Hex Spark Arrestor Slip-On Exhaust 045556
FMF Q4 Hex Spark Arrestor Slip-On Exhaust 045590
FMF Q4 Hex Spark Arrestor Slip-On Exhaust 042328
FMF Q4 Hex Spark Arrestor Slip-On Exhaust 044398
FMF Q4 Hex Spark Arrestor Slip-On Exhaust 044435
FMF Q4 Hex Spark Arrestor Slip-On Exhaust 045565
FMF Q4 Hex Spark Arrestor Slip-On Exhaust 042346
FMF Q4 Hex Spark Arrestor Slip-On Exhaust 043361
California Proposition 65

WARNING: This product contains chemicals known to the State of California to cause cancer, and birth defects or other reproductive harm. Wash hands after handling. For more information, go to www.P65Warnings.ca.gov.