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Yoshimura RS-4 Stainless/Aluminum Full System

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Yoshimura RS-4 Stainless/Aluminum Full System
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    Yoshimura RS-4 Stainless/Aluminum Full System

    131387

    Our Price: $349.99$689.00

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    Details

      When you’re looking at putting the Yoshimura RS-4 Stainless Aluminum Full Exhaust System on your dirt bike, you’re looking at Yosh’s premium dirt bike exhaust designed for the racer that wants to squeeze every last bit of power out of their machine. The RS-4 Full System starts right at your engine with a tapered header pipe that optimizes exhaust flow for both efficiency and power output.

      Exhaust gas then works its way back into the pentagonal muffler where the polyresonant chamber tones the exhaust note down and pumps up power when you hit the mid and high ranges. Last but not least, the carbon fiber end cap rounds out the RS-4 with a touch of wicked looks and an AMA-approved sound insert that comes installed and ready to meet any race regs.

      Specs:
    • Race-ready stainless steel and aluminum exhaust system for your 4 stroke dirt bike
    • Increases mid and high-end power
    • AMA-approved sound insert comes installed
    • Tapered header pipe optimizes exhaust flow
    • Lightweight aluminum pentagonal canister body
    • Polyresonant chamber lowers decibels
    • Stepped, two-stage baffle
    • Carbon fiber end cap
    WARNING: Cancer and Reproductive Harm - www.P65Warnings.ca.gov

    Yoshimura RS-4 Stainless/Aluminum Full System Reviews

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    WRITE A REVIEW
    4.8 / 5.0
    25 Reviews
    5 Stars
    4 Stars
    3 Stars
    2 Stars
    1 Star
    20
    4
    1
    0
    0
    Value
    4.8 / 5
    Durability
    4.9 / 5
    Ease of Installation
    4.8 / 5
    Fitment
    4.9 / 5
    Performance
    4.5 / 5
    Finish
    4.9 / 5
    Features
    4.7 / 5
    Recommend it?
    Yes (9)
    No (1)
    Value
    5 / 5
    Durability
    5 / 5
    Ease of Installation
    5 / 5
    Fitment
    5 / 5
    Performance
    5 / 5
    Finish
    5 / 5
    Features
    4 / 5
    Recommend it?
    Yes
    Good price good product
    yoshimura is a solid company with a sick product with Rocky Mountains price can’t beat it! 19 kawi got bark!!
    April 12, 2019
    Salt lake , UT, US
    Age: 25-44
    Purchased
    1 year ago
    Gender:
    Male
    Weight:
    101 - 130 lbs.
    Height:
    5'4 - 5'6
    Value
    5 / 5
    Durability
    5 / 5
    Ease of Installation
    5 / 5
    Fitment
    5 / 5
    Performance
    4 / 5
    Finish
    4 / 5
    Features
    5 / 5
    Recommend it?
    Yes
    Definitely worth it.
    Really woke the mid-range up. And the exhaust sound is amazing. Use to ride with earbuds, don’t even think about them anymore. #SoundOfMyPeople

    -m-2015 YAMAHA YZ450F--
    April 5, 2019
    Spanish Fork, UT, US
    Age: 15-24
    Purchased
    1 year ago
    Gender:
    Male
    Weight:
    161 - 190 lbs.
    Height:
    6'1 - 6'3
    Value
    5 / 5
    Durability
    5 / 5
    Ease of Installation
    5 / 5
    Fitment
    5 / 5
    Performance
    5 / 5
    Finish
    5 / 5
    Features
    5 / 5
    Recommend it?
    Yes
    Awesome product great price
    Awesome product easy to install and great price

    -m-2012 KAWASAKI KX250F--
    March 29, 2019
    Noblesville , IN, US
    Purchased
    1 year ago
    Value
    4 / 5
    Durability
    4 / 5
    Ease of Installation
    5 / 5
    Fitment
    5 / 5
    Performance
    4 / 5
    Finish
    5 / 5
    Features
    5 / 5
    Recommend it?
    Yes
    Good System
    Yosh System was very easy to install. I didn’t weigh the system, but it isn’t too much lighter than OEM. Definitely sounds better than OEM, but it’s far from loud which I like. Power Gain? Maybe. Probably. It does backfire when off the throttle and decelerating. I thing the ECU may need to be re-mapped to eliminate that. All in all I’m happy.

    -m-2019 HONDA CRF450X--
    Good system 
Easy install
Not that much lighter than OEM
ECU may need to be flashed.
    Good system Easy install Not that much lighter than OEM ECU may need to be flashed.
    January 27, 2019
    Encinitas, CA, US
    Age: 45-64
    Purchased
    1 year ago
    Gender:
    Male
    Weight:
    161 - 190 lbs.
    Height:
    5'10 - 6'0
    Value
    5 / 5
    Durability
    5 / 5
    Ease of Installation
    4 / 5
    Fitment
    5 / 5
    Performance
    5 / 5
    Finish
    5 / 5
    Features
    5 / 5
    Recommend it?
    Yes
    Great value in a full system
    Looks great, fits great, and the sound is insane. This thing barks now, sounds so mean. Havent been able to ride it yet to review the power gains but the sound is amazing and expecting good gains. one hang up is it had damage to the threads for the heat shield bolt hole. had to use a tap and clean up the threads to get the bot to start. Luckily i had the tools or otherwise would have been a little mad.

    -m-2018 SUZUKI RMZ450--
    January 5, 2019
    Philadelphia, PA, US
    Age: 25-44
    Purchased
    1 year ago
    Gender:
    Male
    Weight:
    221 - 250 lbs.
    Height:
    5'10 - 6'0
    Value
    5 / 5
    Durability
    5 / 5
    Ease of Installation
    5 / 5
    Fitment
    5 / 5
    Performance
    5 / 5
    Finish
    5 / 5
    Features
    5 / 5
    Recommend it?
    Yes
    Two thumbs up on price and quality
    Two thumbs up on price and quality. Installed in about an hour and looks/sounds much better than the OEM system.
    October 29, 2018
    Greenfield , IN, US
    Age: 25-44
    Purchased
    1 year ago
    Gender:
    Male
    Weight:
    191 - 220 lbs.
    Height:
    5'10 - 6'0
    Value
    5 / 5
    Ease of Installation
    4 / 5
    Fitment
    4 / 5
    Performance
    5 / 5
    Finish
    5 / 5
    Features
    5 / 5
    Recommend it?
    Yes
    Love the look and power increase
    Looks great and really does add some muscle. I thought the back tire was just hooking up super good but really the front end kept want to come up because of the extra bit of power. Sounds great but I do think the muffler is a bit heavy although you don't feel it as you ride. 2015 RM-Z450's perfect match

    -m-2015 SUZUKI RMZ450--
    May 28, 2018
    Santee, CA, US
    Age: 25-44
    Purchased
    over 2 years ago
    Gender:
    Male
    Weight:
    221 - 250 lbs.
    Height:
    5'7 - 5'9
    Value
    5 / 5
    Durability
    5 / 5
    Ease of Installation
    5 / 5
    Fitment
    5 / 5
    Performance
    5 / 5
    Finish
    5 / 5
    Features
    5 / 5
    Recommend it?
    Yes
    Great exhaust
    This is not just a great value but a great exhaust period. Titanium might be a bit lighter but never holds up to stainless. When titanium gets hot it dents very easily. My last Ti exhaust had little dings in the head pipe after 2 races. If you’re rich and can replace Ti parts all the time go for it, otherwise this is the pipe for the masses.

    -m- KTM--
    March 5, 2018
    Murphys , CA, US
    Purchased
    over 4 years ago
    Value
    5 / 5
    Durability
    5 / 5
    Ease of Installation
    5 / 5
    Fitment
    5 / 5
    Performance
    2 / 5
    Finish
    5 / 5
    Features
    3 / 5
    Recommend it?
    No
    Looks aren't everything
    It looks good and fits well, but didn't notice any power gain from this pipe. It was disappointing, because I've had yoshimura systems before that worked great.
    November 8, 2017
    Hustisford, WI, US
    Purchased
    over 2 years ago
    Value
    4 / 5
    Durability
    5 / 5
    Ease of Installation
    5 / 5
    Fitment
    5 / 5
    Performance
    5 / 5
    Finish
    5 / 5
    Features
    5 / 5
    Recommend it?
    Yes
    Top notch quality
    The quality/fit&finish on this is fantastic. Installation was super easy, and the fitment is perfect. Noticeable power gains (with my engine package, at least), and quieter than stock...absolutely nothing bad to say about it.

    -m-2015 YAMAHA YZ250F--
    January 1, 2017
    Denver, CO, US
    Purchased
    over 3 years ago
    Show more
    Rocky Mountain ATV/MC gift card Each question or answer submitted enters you into a:
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    Start typing your question and we'll check if it was already asked and answered. Learn More
    Browse 13 questions Browse 13 questions and 21 answers
    Does this full Yoshi exhaust (2015 KTM 350 SXF) come with a removable spark arrestor insert?
    Mike M on Nov 27, 2016
    Does the Yosh RS-4 Stainless/Aluminum Full System for a 2019 Honda 450x come with a spark arrestor?
    A shopper on Jan 10, 2019
    BEST ANSWER: Yes it does. But it has a another insert installed from the factory you will have to take it out and put it in. Mine was a pain to get out.
    Do I need to change my mapping with this exhaust. I run the standard mapping now. I have a 2019 rmz450?
    jason s on Apr 20, 2020
    BEST ANSWER: My brother and I both put that exhaust system on our 2015 rmz450 and did not change the mapping. We are both very pleased with the RS-4 full exhaust system.
    is this the full exhaust system? Like the header to all the way back to the back guard ?
    A shopper on Feb 6, 2018
    BEST ANSWER: Yes it is! Its nice. The new muffler is not completely compatible with stock header, fyi. But it is a full system so no worries.
    Will there need to be any tuning or remapping for a 2018 yz250f?
    A shopper on May 1, 2018
    BEST ANSWER: No, it’ll run fine with the factory mapping and sound much better than a factory exhaust
    is this the full system header and pipe ?
    A shopper on Mar 21, 2018
    BEST ANSWER: Yes I bought it for a 2015 KTM 450sx-f factory edition and I got the FULL SYSTEM.
    Note it says Stainless/ Aluminum Full System ^
    Header is stainless and the canister is aluminum
    Does the system that fits a 2019 KTM 250 SXF also fit a 2019 KTM 250 XCF?
    Logan B on Sep 18, 2019
    BEST ANSWER: We do not have this part available for the 2019 250 XC-F, so unfortunately we can not compare part numbers at the moment.
    Is this the FS SS-AL-CF?
    A shopper on Aug 14, 2018
    BEST ANSWER: I would be happy to get check this for you. What is the make, model, and year of your machine?
    Will this pass ama and fim inspections at the nationals?
    Joshua B on May 14, 2018
    BEST ANSWER: AMA-approved sound insert comes installed
    Can I run the yoshimura in the woods ?
    Randy on Mar 4, 2018
    BEST ANSWER: It depends on your state. Each state has different off road regulations, you will have to see what those are and read the product details.
    This full exhaust fits on kx 250f 2009?
    A shopper on Apr 28, 2017
    BEST ANSWER: To see if this part will fit your machine please enter the make, model, and year into our "Choose a vehicle" drop down boxes found above the product image. If your machine is not listed, we may not carry the right item for your application. If you have a 2017 year model but don't see your machine as an option, please contact a tech via Live Chat or call us at 1-800-336-5437 for assistance.
    I bent my yoshi header pipe, can I purchase just the header pipe?
    Tyrone K on Mar 27, 2017
    BEST ANSWER: Unfortunately we do not sell the Yoshimura header separately. I believe Yoshimura sells it separate and you may want to contact them.
    2009 crf 450 full yoshi system where can i get spark arrestor insert ?
    A shopper on Jan 22, 2017
    BEST ANSWER: We don't carry a spark arrestor for this exhaust, but the MFG number for the spark arrestor is #SA-04-K.
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