2020 YZ450F FMF 4.1 vs. Stock Exhaust

I installed a FMF 4.1 slip on exhaust on my 2020 YZ450F. Here is a short video of the installation and sound comparison.

[@williamgoske1178]

Awesome. Lil man looked happy to help

[@barrybaker9173]

That little kid is so cute!! You know he enjoyed every minute of it.

[@jeremy_moto_192]

sick bike and beautiful exhaust!

[@Blade_RunnerZR1]

I thoroughly enjoyed this video.

[@harrylois7506]

And so did the lil homie with the bike 😍🔥

[@amoore2165]

Good job on the video. Well edited. And cute. And informative. Sounds more throaty and looks meaner with the new one. Almost a shame to cover it up with the plate.

[@lister4life]

Heerlijk hoe je haar zo op het krukje tilt

[@lautaroastudillo6168]

This bike it's amazing!! Enjoy it!! Greetings from argentina!!

[@chrishansen8026]

Lautaro Astudillo shaloam

[@450brucey2]

the dopest part is your little you helping you as much as he can and seems to enjoy it 🤣🤣😂🤣

[@aftermathmotomxrc]

Love the Mechanics Helper!! #coolkid

[@HighSpeedTV]

great video!! thanks!!

[@aniketwaghmode4742]

Fmf exhaust sounds good

[@dylanmacleod6589]

Hey nice 450 man. I just bought a 04 YZ450f yesterday for $1800 from a guy that basically bought it new and never rode it. Still originally frame paint everything. If you seen a picture you wouldn't believe the shape of it for $1800. I'm a 2 stroke rider by heart but I'm not gonna like I'm loving this 450. My 01 YZ125, and 99 KX250 both top out at 70 max where the 450 will go close to 100. There's no competition there haha. Keep on riding brother!

[@AndrewDeVries211]

That’s awesome! Some day I’d like to find 99 kx250 to restore. My dad had one when I was a kid. I always thought that bike was so cool with the green frame.

[@stopibeastin7196]

Tru

[@mukkiiieeeee]

Nice garage

[@dentgent768]

Need the gray acerbis plastics for sure

[@ajmotocross]

was it worth the money spent? increase in power? i am debating on getting one. I need feedback

[@garrett3234]

i got to like the vid for the simple fact i too at one my point was a young blonde haired kid on my pw50

[@twowheelpilot]

Sounds exactly the same to me. Does anyone know where I can buy a second hand stock 2020/2021 YZ450F pipe from? No luck with ebay so far. Thanks I'm advance if anyone has any information. Regards

[@Yz250fx]

Was there much weight difference?

[@lhr_arms]

wrum, wrum 👍

[@CRFDAD76]

Nice to see Father and Son working together. It’s how they learn..... nice organized looking shop by the way. Also, what was the power difference with the new exhaust?

[@450brucey2]

Not much less than 1hp which is nothing

[@djdanfetish1]

Brothers just bought this for his husky 450 from holeshot mxshop UK . test it tomoz at track ..

[@nattaponphuangsriraksa3729]

Introduction song ?

[@Jake_Hynds]

Jeez the valves on that bike are disgustingly loud

[@RaptorVlogz]

I thought the same thing !! All the 450s I have rode have not sounded quite that loud.

[@Jake_Hynds]

@@RaptorVlogz right .. also if your going to do a sound test we want to hear the rev limiter not a 16th of throttle

[@josephfoster3819]

My 06 yz450f had loud valves like that too . And I've heard of other people having the same thing on their Yamaha's

[@Jake_Hynds]

@@josephfoster3819 yea the valves are loud on my wr and also other bikes .. just this one seems excessive.. also notice it alot on ktms have a distinct valve noise but sound different then the yamis

[@t-train6534]

My kx450 seems like the valves sound really loud on video but irl they seem quiet

[@johnmatajy6639]

Where did you order this exhaust from

[@vivoY-im3vi]

I like

[@febroczen4339]

First music?

[@walterprade1851]

Hi Andrew, what heat resistant silicone do you use for the slip on exhaust connection?

[@626weekendwarriors9]

I’ve used Permetex high temp silicone (BLACK). It works great for this application.

[@jovannynunez690]

Lucky kid 🙂

[@zackbravierre6235]

Music video?

[@pipefitterdirtbikerider3013]

Does the FMF make a difference

[@jfratis9081]

I swapped the kill switch and map switch. The way they come stock makes no sense.

[@EctoGamer]

It does kinda, its maybe more comfortable for him

[@ravyvanna9030]

Good

[@hristodonchev5911]

Hi, I am interested in buying the factory muffler you have changed. Do you still have it and if you do what is the price? Thank you

[@AndrewDeVries211]

I sold the bike and exhaust already. Sorry. Good luck with your search

[@sebastianvalenti3726]

Cómo se llama el tema/canción?

[@crowmrf02]

Yamaha semakin di depan gaspoll

[@hencetirta7633]

TAPI HONDA FINISH LEBIH DULU

[@crowmrf02]

@@hencetirta7633 hahahaha

[@mariomurillo2353]

I like the music n little kid

[@76tigga]

can you feel a power difference after the FMF install?

[@AndrewDeVries211]

More bark down low. Nothing crazy. You can make more noticeable changes in the power tune app.

[@John-iv8gt]

How’d you get the stock header guard back on? When I try to install it seems to big now since the fmf pipe diameter must be a tad smaller?

[@AndrewDeVries211]

Add me on Instagram. I’ll send you a pic of guard later today. @devries211

[@nolanvitoo1340]

God bless me to buy this in 2021

[@toddrobison8929]

Shoulda bought the full system instead of the slip on. But most reviews on the 2020 said they dont need an exhaust. Potent enough in stock form

[@aftermathmotomxrc]

SUPER POTENT

[@fmsmark66]

I have a 2020, and power for days!

[@ParaMoto910]

Bro buy the full fuckint system you gotta buy the front pipe like the second half lol

[@slabdaddy4209]

Giver some pepper!!🤕🤕🤭🤭

[@noahvaneyck598]

Hey Andrew, are you dutch? Cause your last name sounds dutch

[@remcodw2257]

Klinkt wel Nederlands ja

[@pauloyoshizaki2103]

YAMAHA : YZ 450 F : MOTOR 4 TEMPOS : TOP DA CATEGORIA : POTÊNCIA : AGILIDADES : LEVE : ARRANQUE FANTÁSTIC : MELHOR : TOP YAMAHA .........

[@dominickjohnston5881]

Nasty cam chain tick

[@sebastianvalenti3726]

Nombre la canción ICE TEA name the music ICE TEA

[@mariomorales916]

Cuanto cuesta la moto peso colombiano

[@YAMAHAmx730]

Happen to notice it overheating fast? Just installed one on my 19 450fx and started it let warm up and gave it a few revs and noticed it boiling antifreeze and out the overflow. Bike’s brand new haven’t even rode it yet

[@blugods2655]

RustyBrown730 did you try the same thing with stock exhaust?

[@YAMAHAmx730]

*Blu Gods* yeah! I’ve started it and let it sit and warm up and rev it up a bit just to get it warm. Not any issues. But put the fmf on and took out to listen to the difference. Same thing I’ve done with stock pipe. And it got warm enough to hear coolant boiling and out the overflow.

[@slabdaddy4209]

@@YAMAHAmx730 get a suzuki!!😂😂🤣🤣

[@blugods2655]

Torn between this a yz250 2 stroke

[@jaredthompson8188]

What type of riding do you do and are you your own mechanic?

[@blugods2655]

Jared Thompson got a ‘16 yz450

[@mdjabedmiah1128]

I hate the fact that it's pretty much same as the stock ☹️

[@ParaMoto910]

Because he just got the slip on not the full system

[@otavioaugusto6751]

Acelera essa moto igual homem caramba

[@henriquetrevisan4160]

Nossa mano que angústia ver esse maluco com perreco

[@birdiges]

Some people have too much money and time on their hands...

[@mattjones1792]

Should of gotten the whole system not just the slip on

[@shaz3796]

I have blown ear drums thank a lot

[@newthonsflax4154]

No many diffrent.. 😊

[@leithal4116]

Rev the bloody thing

[@jamespietronico971]

Yeah I heard of you give it full throttle they break jez bud it’s a dirtbike

[@Jake_Hynds]

Lmao right ... how about actually rev it.. prlly rides it the same way

[@dustinrichards8401]

Yamaha is the best

[@halimkerras6760]

كاش وحاد لبيع

[@user-il3em4yi3q]

🤔

[@antoniomb8987]

That's not a damn sound check 😒

[@marksommerville5857]

That's a muffler. Exhaust is the front pipe!

[@johnbednarz1424]

Doesn't sound any different

[@eatnpooter1634]

Looks heavy 😑

[@jesusgarciaa3652]

Stock sounds better

[@BobWilson84]

2 strokes are better.

[@jaxbeach09]

Sike

[@connorg.8878]

So gay shouldve red boomed it