400ex Dyno Tuning and New Exhaust

In this video we finally upgrade our 400ex's stock exhaust with our new Rossier R4 full exhaust system. We also did a full dyno session comparing each stage of the process. I'm super stoked with how well the numbers and performance came out. Jay did an awesome job tuning as always! Shout out to Rossier for making a great looking and sounding exhausts!

2004 Honda 400ex
Motion Pro +2 Throttle Cable
Motion Pro 1987 Honda 250x Clutch Cable
Factory 43 front bumper
Alba Nerf Bars
Alba Gas Cap

Chapters
0:00-0:56 Intro
0:57-1:40 Exhaust Unboxing
1:41-2:16 Stock Exhaust Notes
2:17-2:37 Illinois Powersports
2:38-4:19 Base Power Numbers
4:20-5:39 No Airbox Lid Numbers
5:40-7:33 Installing New Exhaust
7:34-8:59 Rossier R4 First Numbers
9:00-15:11 Fine Tuning Carburetor
15:12-18:10 Final New Numbers
18:11-21:30 First Ride Impressions
21:31-22:41 Outro

Music sourced through epidemic sound
Closing song "Murky" by Cushy

Camera Gear-
Iphone 13 Pro for Cinematics

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#savesportquads

[ALDA]

It's insane how much fun the old 400ex still are with all these new 450s being able to have 2x the power I still have my 1999 bug eye and even tho my 2021 yfz450r is in the 60s hp range now days I still have as much fun riding the 400 as I do the 450 tbh I sometimes enjoy the 400 more and Jay and Illinois power sports are great I live in Dekalb Illinois and Jay has dialed in all my machines and I've been very pleased with the work

[jamiesmo]

That 400ex is a nice machine, sounds great with that pipe. Can't wait for the next video of you ripping the thing with the new set up 🤘🤘

[t-money]

I love it, love it, love it. Florida Boyz can't wait til you come back so we can see this bike in person.

[smr]

Ah man, i couldnt wait...finaly the Rossier on the TRX400, now its a dream trail machine.. looks really good ;-) thanks for the treat!

[andrewspoto]

Wow! What a difference in sound, and I am sure the power is insane. Like always nice work…..

[timpence]

Great video Pete. Jay is the man for tunes. Well worth the drive for sure. 9 to 10 hrs for me but was worth it. Those Rossier r4 sound so sweet.

[nathanlarocque]

Got the same pipe for my Dvx 400. Sound so good!!

[nathanaelruizm.]

Clean build always makes the cleanest builds

[unitymixer]

This is the best you can reach whit 400ex and keep 100% of the motor safety in the long run.

[tylermatheson]

Great video as always absoultly love that ur doing 400ex videos keep them coming, I need to get mine on a dyno soon, keep it up cant wait for top quad videos 🤙#savesportquads

[bradmcdaniel]

That's awesome brother I like the new sound, the sports shop is great 👍😎

[jamisonsenitz]

Pete your Killin the 400ex content dude!!! Have a 04 400ex 1mil over fmf pipe and k&n filter, so need to get it dyno tuned now. Great vid

[chriscook]

I got mine in a few weeks ago for my 400 and I wasn’t disappointed one but I hated waiting for it so worth the wait David’s exhaust is top of the line👍

[floridatrailrider]

Pipe sounds great, the 400ex is coming out really nice 🤟

[BrewerOffroad]

Love the sound of the R4 on the 400ex. Might just have to get me one for the 07 build!

[bionicdrxamsyt]

i was the first like on the vid pete keep up the good work i watch all the vids man love the yfz450

[LiveFreeOrRIP]

Dude I LOVE my 2007 400ex. Its absolutely my favorite trail atv yet. for sport bike that is. Ive ridden and owned a TON at this point. I can ride my 400 all day and im NOT tired. I ride my 450 i had and it was BEAT TO DEATH after 2 hours... Same for raptor. its just odd... The raptor is a great bike but it beats the shit out of me for some reason. Its like a workout to ride. 400 is Super easy to ride and it dont wear me out AT ALL...

[fearoshima]

@Pete Hager the Honda can be compared a bit to a stock raptor when it is tuned

[Itsjake]

It’s really interesting how the previous owner striped down the quad just to paint the frame but left everything else pretty much stock. Nice to see you doing these tasteful mods & btw I’m A big fan of OEM graphics although you’re probably going to yank them off haha

[rRaptorLife]

Oh no no it sounds a whole lot better when u see it video don’t give it no justices that’s one badass 400ex