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4-Stroke Exhaust4-Stroke Exhaust

4-Stroke Exhaust from Rocky Mountain ATV/MC

Exhaust systems in either full race or with tuneable spark arrestors and different tips to give you that perfect power output for either motocross or trail riding.

Latest Dual Sport 4-Stroke Exhaust Reviews – You could win up to $500 for reviewing products!

  • Polaris Stage 2 Upgrade Kit

    Polaris Stage 2 Upgrade Kit

    Derek in CO

    Havent completely installed kit yet

    The exhaust on this kit is perfect. Increase exhaust flow and sounds throatier, its not annoying loud. If anything this is the upgrade to get. I am excited to see how the cams are going to do once installed.

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  • FMF Hex Q4 S/A Silencer

    FMF Hex Q4 S/A Silencer

    JEFF in CO

    14 yz 250f

    This pipe is nice and quiet. It seems to choke the bike up a bit. I haven't fine tuned the EFI yet. The fit and finish is very good, but it's about six inches longer than the stock pipe and will probably get damaged in a crash on the right side.

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  • FMF Power Core 4 Hex S/A Silencer

    FMF Power Core 4 Hex S/A Silencer

    Sam in CO

    Great pipe for a great price

    If you've mangled your pipe in a crash, look no further. This is a great pipe at a great price. I can't say one way or another about any power increase as I've never ridden my bike with an OEM pipe, but I wouldn't hesitate to buy FMF again. Only complaint is that the "graphics" on the pipe scratch very easily and the graphics on one side peeled completely off.

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  • FMF Factory-4.1 RCT Stainless Steel Silencer

    FMF Factory-4.1 RCT Stainless Steel Silencer

    jeromy in NE

    instant performance upgrade

    Besides the coolest exhaust note yet: this along with the FMF Grunt added imediate & noticable improvement in the throttle response & low end for my bike over the stock silencer. I hope I don't have to but I'd purchace it again. I typed FMF grunt when meaning FMF Snap.

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  • SLP Super Silent Muffler

    SLP Super Silent Muffler

    Tim in Idaho

    Great Muffler

    Took some time to install and the pictures were not that great. It is quieter than the stock muffler. I would recommend it.

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  • FMF Power Core IV S/A Silencer

    FMF Power Core IV S/A Silencer

    Roger in IN

    Great muffler

    This muffler looks awesome, sounds excellent. Sound at idle is just a little bit louder than stock. When you get on it it is about 20-30% louder than stock. It sounds great. Good improvement gain. I installed this muffler, the fmf power bomb, and the fmf power management in about 45 minutes. Huge difference. Great power gains

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