Best YFZ450/R Exhaust: Various Setups

The YFZ450 and 450R? A total beast, man. That’s the ATV packing the best power-to-weight ratio out there.

The question is, should you let it roar or be more modest? Both work fine. This Yamaha masterpiece is 100% pure fun even when purring on a modest setup.

There are several options I’d consider the best YFZ450/YFZ450R exhaust. Here’s a quick overview:

➥➥ Best well-rounded pick: Yoshimura Signature RS-2. Not the loudest, but balanced in its power and sound distribution. Lighter than most other exhausts, too. Perfect for the majority of YFZ450/R fans.

➥➥ Best budget option: Definitely Big Gun’s ES Series. Twice cheaper than competitors, it still packs a respectable punch. Decent HP boost, spark arrestors included, and sturdy for its price. Drawback is the 1-year warranty.

➥➥ Best loud & tuning-ready pick: FMF Factory’s 4.1 Series. Very underrated. Its shorter size centralizes mass and keeps it safe from damage. The louder, deeper growls paired with extra tuning capabilities make it a must-have for noise maniacs.

In no way are these three the only viable picks. However, I feel they fit their intended purposes the best considering their price point too. Other YFZ450 or 450R exhaust options can be:

• Dasa
• Rossier
• Monster
• Barker’s
• HMF

Speaking of the Yoshimura RS-2 Signature series I recommend, here’s a neat video showcasing its true sound:

Let’s talk about something important first, before I continue looking at these picks under a magnifying glass. You can use the Table of Contents to jump to your preferred sections:

Alright, here’s the deal. A lot of people don’t consider the various factors involved in grabbing an exhaust for your Yamaha YFZ450/450R.

Are you going to hit the trails with it, speeding like a maniac? Or are you up for some riding fun in the dunes, revving it up in the sand?

There are some people who also dig riding their ATV in a more urban environment too.

…which is where noise limits and city regulations come into play too.

Take Dasa YFZ450 exhausts for example. Without a doubt, they’re top-of-the-line loud and powerful. However, in sound-controlled areas, you’re going to be breaking the law.

Not only this, but for some, they will be too noisy. They can work pretty well with other mods and pack an HP boosting punch, for sure.

I got my top 3 picks exactly thinking about notable details like these. Let me expand a bit more on each of these, starting with the Yoshimura RS-2.

Yoshi’s RS-2 system has been a staple for most Yamaha ATVs, including the classic Raptor 700. There are many reasons why, but I’ll list the ones I feel resonate with me the most.

Note: You can check the first gen (2004-2009 YFZ450) Yoshimura here. For the 2010-2013 YFZR/YFZSE option – it’s this one. Shop around for 2013-2023 options.

First things first: Yoshimura basically pioneered their trademark pyramidal shape. It doesn’t look like much, but the geometry here allows for a better flow on more controlled noise levels.

Basically, you get performance without the exhaust running too loud. Yoshi is 100% sound-compliant for controlled areas despite its larger core.

At the same time, the construction here is a beauty. Lighter due to its aluminum build, the RS-2 Series is fully made in the US. The mounting bracket is extra durable so the exhaust is secure even in harsher environments.

Yoshimura’s YFZ450/R exhaust systems aren’t HP-fueled beasts. However, they pack a punch, have great looks and finish, and are perfect for the majority of OE to light mod setups.

Yes, you also get a 100% compliant spark arrestor kit too.

Not everyone wants to be tame with their Yamaha ride. And, of course, there are quite a few people who can’t shell out several hundred bucks for an exhaust.

Here’s where the Big Gun ES Series (budget pick) and the FMF Factory 4.1 Series (power & customization) kick in.

Let’s start with the Big Gun first.

On paper, this one sounds iffy. How do you get something made in the US that still features aluminum and packs HP and torque…

…on half the price?

Well, the biggest drawback here is the shorter (1-year) warranty. The chamber design isn’t as intricate as Yoshi too, for example. So the sound won’t be as balanced on various RPMs as other, higher-priced options.

Still, the Big Gun has an insane value-for-price ratio. It’s also lighter than stock to help your YFZ450/R ride nimbly. You get the much-needed spark arrestors too, though they’re screen-type here.

I wouldn’t use the Big Gun on the dunes, but it sure is great for trails, more urban areas, and the other usual suspects when it comes to enjoying your YFZ450/R.

What about the much more premium FMF 4.1 Series?

As I said, this one’s an underrated gem. Lots of people talk about Rossier, Dasa, Barker’s, and the other big names in Yamaha’s ATV scene.

Sound, power, tuning freedom. These are the key aspects of what makes FMF great.

If you’re one of those acoustics fanatics, the Factory 4.1 Series will outshine comparable exhaust options. The RTS (Rapid Tuning System) tech here makes it very easy and intuitive to tinker around with the tuning.

To add to this, the 4.1 Series has stepped up in terms of sound levels and noise distribution mechanics too. FMF’s Resonance Chamber Technology rivals Yoshimura’s approach and delivers louder sound with an equally balanced profile.

One very specific benefit of the 4.1 Series is the shorter exhaust design. This allows the muffler to inch closer to the motor (centralizing the mass).

Most importantly, though, it keeps your several-hundred-of-bucks-investment safer. In case you hit something, the FMF will be less vulnerable to damage due to its more compact size.

A great exhaust for both the YFZ450 and YFZ450R, no doubt. Best for sound maniacs who will ride their ATV in extreme terrain too.

As I said, the three options I discussed are far from being the only ones. There are a bunch of respected brands with decades of history of making Yamaha ATV-ready, kickass exhausts.

From what I’ve seen on discussion boards and around me, people seem to also dig:
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• Dasa: Lots of color options available, as well as a shorty YFZ450 canister length option too. You can check the available products here.
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• Rossier: Their site might look too barebones, but these guys have earned tremendous respect for their setups on YFZ450 or Raptor 700 ATVs. Check their exhausts here.
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• Barker’s: Contrary to Rossier, the team over at Barker’s has a lot of info on their exhausts. You can check the applicable setups here. I’d say they’re pretty comparable to what Dasa makes for the YFZ450R.

So, all of these brands have applications for both generations of the good ol’ 450.

If you’re new to the scene and wonder what changed (and when), here is the gist of it:

Think of the YFZ450 as the first gen of the YFZ450 family. It ran up to 2009 when it was succeeded by the YFZ450R.

The letter ‘R’ doesn’t really paint the full picture of some pretty major changes.

Fuel injection put aside, the updated YFZ450R features long travel suspension and an aluminum steel frame that boosts up its overall performance. The width of the ATV was also buffed up quite a bit.

Regarding ride feel, a huge improvement is the radical changes to the front-end design. The geometry changes allow the YFZ450R to achieve vastly better cornering compared to the YFZ450.

Some other differences are applicable too, but these are the most notable ones.

In any case, if you’re running a specific setup – be it YFZ450 or YFZ450R, let me know. I – and the readers here, would be glad to hear your own experience and observations.

Is the YFZ450 not the only Yamaha in your riding fleet? Check some other guides I have, such as the Yamaha Blaster carb post. In the near future, I’d like to write something on the absolute unit that the Grizzly is too.