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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!

  • FMF Hex Q4 S/A Silencer

    FMF Hex Q4 S/A Silencer

    Zach in IN

    nice improvement

    A huge improvement over a stock WR exhaust. removeable spark arrestor is nice. The only downside is that the FMF decal on the back is a poor design. Both mine and my buddy's have already came off in about 6 months time.

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  • Polaris Stage 2 Upgrade Kit

    Polaris Stage 2 Upgrade Kit

    Derek in CO

    This Kit is worth the money!

    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. Amazing how much power this kit increases the RzR. I love it!

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  • Lexx MXe Slip-On Silencer With Mid-Pipe

    Lexx MXe Slip-On Silencer With Mid-Pipe

    chuck in Colorado

    good bang for the buck

    have had this exhaust on my klr-650 for a year, It was easy to install, fit nicely, looks good. It was a little louder than I expected with the silencer installed. Would like to tone it down a bit but no additional option to do this is available. But the product is a good one, priced right, lighter than stock by a few pounds but a good buy...

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  • FMF Power Core IV S/A Silencer

    FMF Power Core IV S/A Silencer

    Helmut in VIC

    After Race Map this is another Improvement ...

    cant beat the price and great performance .

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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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