Yoshimura RS-4 Full System Exhaust

$551.99 - $994.99
$491.99 - $845.99
4.50 out of 5 stars
Fitment Expert:
Dirt Bike Dirt Bike UTV Make Year Model
Yoshimura RS-4 Full System Exhaust
Yoshimura RS-4 Full System Exhaust
  • Description
  • Reviews (6)
  • Q&A (5)
  • Fitment

The work that went into developing the RS-4 muffler design paid big dividends in 2010 with Ryan Dungey winning the AMA 450 Supercross and Motocross Championship series as a rookie in the same year, and again in 2012 with the Yoshimura-backed GEICO Honda team winning both 250 Supercross Lites titles. That same R&D has been directed to developing the current generation RS-4 - a unique design that provides an unrivaled combination of power and a quiet exhaust note. The RS-4 features a polyresonant duplex chamber, a two-staged stepped baffle and an innovative carbon cone end cap.

  • Pentagonal-shaped muffler sleeve and aluminum mount bracket.
  • Front muffler cap functions as a polyresonant chamber which helps reduce noise.
  • Two-stage stepped baffle.
  • Durable high-grade stainless steel tapered header and mid-pipe.
  • Considerable weight reduction.
  • Carbon fiber end-cap comes with a U.S.F.S.-approved spark arrested insert installed in the muffler.
  • Step-by-step directions and all necessary hardware included for an easy installation.

Yoshimura Exhaust Series Descriptions:

Enduro Series: In the mid 90's Yoshimura didn't go to the dirt; the dirt came to Yoshimura. Enduro Series systems are an evolution of Yoshimura's early off road efforts crafting off-road exhaust systems. The Enduro Series are all equipped with U.S.F.S.-approved spark arrestor, forest-friendly noise levels, and are tailpipe emissions compliant. (CARB/EPA tail-pipe emissions compliant; all applications are marked with appropriate EPA noise emissions labels.)

Race Series: If you're looking for that competitive edge, look no further than Yoshimura's Race Series. These exhaust systems are designed with nothing but power in mind. Each Race Series system is developed in accordance with noise compliance regulations imposed by most racing sanctioning bodies worldwide. FOR CLOSED COURSE COMPETITION ONLY; NOT INTENDED FOR STREET USE.

Signature Series: Introducing Signature Series by Yoshimura - an offering of exhaust systems that a dealer can install with confidence. The Signature Series lineup is the answer for today's dealer who is faced with a challenging marketplace. The applications for the Signature Series line cover the entire powersports spectrum, including many off-road applications. Everyone of Yoshimura's Championship Winning Motocross exhaust systems and nearly all of the ATV / Side-by-Side applications are all members of the Signature Series Family. All Signature Series components are tested, documented, and marked as required by federal and state regulations. (CARB/EPA tail-pipe emissions compliant; all applications are marked with appropriate EPA noise emissions labels and certified by an independent laboratory for EPA noise compliance.)

4.5 out of 5 stars (6)
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1-6 of 6
Overall 5 out of 5 stars
Location: Honolulu, HI, USA

Fits perfect for a 2015 WR450F, easy installation. Great sound and outstanding power. Very responsive, I could keep my front light when needed to on the trails. The exhaust came with a cool Yoshimura plug and some stickers :)

Overall 2 out of 5 stars
Verified Purchaser
Location: Costa Rica
Badass sound and look, period.

Intermediate vet, rmz250 2015, did one heat with stock, then replaced it with yoshi and did another heat; no gains in time. Had to use a leaner coupler with yoshi, with the stock one was slow.
My impression is the besides the badass look and sound there is very little difference compared to stock; I felt imrovment in hi revv but less low-mid range.
Very easy to set and to remove; I put the stock back and I have the yoshi for sale now.

Overall 5 out of 5 stars
Verified Purchaser
Location: menifee,ca
Good buy

fit great on my 2012 crf 250 sounds great Bike revs faster the head pipe is the same as stock with out the heat shield so save some money and get the slip on system

Overall 5 out of 5 stars
Top 1000 Contributor
Location: Cimarron,KS
Sick as heck!!!!!!

this full exhaust system is da stuff!!! quick & easy to put on! sounds very nice! and omgosh power everywhere now! comin out of a turn and pinn the throttle your front tire will be lifting up!!! GREAT PIPE!!

Overall 5 out of 5 stars
Ease of Installation
Location: Kopperston WV
Even touchier throttle response

power increase and even touchier throttle response from top to bottom, my RMZ250 now sounds more like a 450, revs longer in 5th and brings front wheel up in higher gears when needed, very tight fit under side panels but no problem, first after market pipe that I have ever bought that actually gives noticeable power increase with installation, awesome pipe, awesome results

Overall 5 out of 5 stars
Ease of Installation
Location: Pa
Awesome Exhaust Upgrade for the CRF450R

Awesome Exhaust for New CRF450R ! The sound is better and not as loud as stock minus a few decibels.The power is better and looks sick on bike.

1-6 of 6
Total Questions (5)
Questions with answers:
Questions without answers:
1-5 of 5
BB101 2 months 24 days ago
I have this exhaust for a 2010 crf250r. Will it fit a 2012 crf250r?
MotoSport Staff Expert
2 months 24 days ago
No the Yoshimura RS-4 Full System Exhaust from your 2010 Honda CRF250R would not fit the 2012 CRF250R.
bil1s Over 6 months ago Location: quebec
How many db with a yz450f ?
Expert MotoSport Staff
Over 6 months ago
Sound For: 2012 YZ450 OEM: 96.0 dBA 99.1 dBA Yoshi w/ AMA sound insert: 95.8 dBA – dBA - Installed Yoshi w/ Spark Arrester: 95.8 dBA 98.1 dBA - Optional
scoobydoo2203 Over 5 years ago
Does the comp 4 come with the carbon fiber tip on it on a 2009 crf 450?
MotoSport Staff Expert
Over 5 years ago Location: Portland
Yes, this does have the carbon fiber end cap.
shane195 Over 5 years ago
What is the difference between this and the rs2??
Over 5 years ago
the RS4 is for the new 09 and 2010 Honda's. The picture shown is wrong for and RS4. I told motosport this along time ago when i orders my RS4. On a different note the system is fabulous on a 2009 crf 450r
Top 25 Contributor Top 10 Contributor
Nichro Over 5 years ago Location: Mays Landing, NJ
Is that the correct exhaust in the picture?
MotoSport Staff
Over 5 years ago Location: P+RTLAND
This is just a general product picture supplied by Yoshi. So the exhaust may vary from the picture depending on what bike you have.
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