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

  • FMF Power Bomb Header Pipe

    FMF Power Bomb Header Pipe

    James in AZ

    FMF

    Great product! I desert race and this has held up to extreme abuse and really made a huge powerband difference in my Yamaha. I used to run the Trinity racing System and now run this with a motoworks pipe and it pulls smooth all the way to redline. Great product!!!

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  • FMF Power Core IV S/A Exhaust System

    FMF Power Core IV S/A Exhaust System

    Brent in ME

    exhaust

    no holes for stock exhaust shrouds in very front but does sound good TECH NOTE: NO HOLES FOR STOCK HEAT GUARD

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  • Toomey Slip-On Silencer

    Toomey Slip-On Silencer

    shane

    toomy

    it has a lot les baffle so it comes through the silencer a lot more eficent and it just sounds better and for every one who is complaining about the one clamp you should of taken medals to learn how to weld!

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  • FMF Power Core IV Exhaust System

    FMF Power Core IV Exhaust System

    sawyer in NJ

    XR100R

    fit on great, exept the gueard that is on the orginal exhaust doesnt fit back on and the sytem gets very hot. but it sounds killer and adds some speed. great buy

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  • Motoworks SR4 G2 Full Exhaust System

    Motoworks SR4 G2 Full Exhaust System

    Skip in IL

    Buy IT !

    I have a 2012 CRF 450 R . The fit and finish of this pipe is as good or better than any other pipe I have seen. The Dyno chart that Motoworks sent me put base line HP at 47.72 @ aprox 8.2K rpm Torque at 31.50 with pipe 50.97 @ aprox. 9.5K rpm. Here is the deal , you could spend 500.00 more dollars to get aprox the same HP and Torque . If you want to be a name dropper go with the big names in MX pipes. Motoworks has a great rep in the AVT world. Also the the mid pipe and silencer is about .8 Lbs. lighter than stock. It really woke the bike up. No I don't have any affiliation with Rocky moutian or Motoworks Buy it and laugh at your snob buddys as you roost by with money flying out of your pockets

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  • Yoshimura RS-4 Stainless/Aluminum Slip-On

    Yoshimura RS-4 Stainless/Aluminum Slip-On

    THOMAS in NC

    What was expected!!!!

    If you are looking more power with minimum spending and doing internal work, this is for you. Put this on my 2012 crf450r. Slip-on gives an immediate increase in power. No need to remap, works out of the box. Couple this with a Power-Flow filter from Twin Air and hold on. Increases pull into mid/upper 9,000 rpm range. When the new power wears off, a re-map and pulling the spark-arrestor will do the trick. Now need to stock up on some fresh tires to put the SCARY back in it.

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