Eli's header

What's the scoop with this enormous resonance chamber on the factory KTM? It has "EVO3" stamped in the front but I wasn't able to dig anything up with a search. Assuming it's another way to quieten down the bike while improving power.

There's the usual resonance chamber further back, but I've never seen a four stroke header like this. 

My first thought was roost damage:

2025-11-05 17-49
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TeamGreen
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11/5/2025 2:55pm

Talk about “Boost Bottle”?!🤣

That scooter makes monster-torque and I’m guessing that mega-chamber has something to do with that. 

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AJ565
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11/5/2025 2:57pm

It was talked about a little bit in PitBits a few months back. KTM tested it before one of the nationals to meet the up coming lower DB levels and Chase and Aaron liked it enough that they went racing with it that weekend. 

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ML512
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11/5/2025 2:57pm
What's the scoop with this enormous resonance chamber on the factory KTM? It has "EVO3" stamped in the front but I wasn't able to dig anything...

What's the scoop with this enormous resonance chamber on the factory KTM? It has "EVO3" stamped in the front but I wasn't able to dig anything up with a search. Assuming it's another way to quieten down the bike while improving power.

There's the usual resonance chamber further back, but I've never seen a four stroke header like this. 

My first thought was roost damage:

2025-11-05 17-49

Red Bull KTM has been running that since late Supercross this year. Yes, it’s for sound and part of their push to get their bike under the incoming 109db test, which has been pushed out until the 2027 season instead of the original plan to use it in 2026.

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avidchimp
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11/5/2025 2:58pm Edited Date/Time 11/5/2025 2:59pm
TeamGreen wrote:

Talk about “Boost Bottle”?!🤣

That scooter makes monster-torque and I’m guessing that mega-chamber has something to do with that. 

It supposedly helps meet sound requirements in EuroLand. Looks like a ding magnet to me. 🤣

EDIT: Still finished on the podium.

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The Shop

Chris_Buehler
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11/5/2025 3:01pm

When I was in the pit at the MXdN I noticed some of the KTM's had those. Maybe Lucas Coenen's? Looked like a damn 2-stroke pipe

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Alex the great
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11/5/2025 3:26pm

That's like 2 stroke chamber status!

Brent
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11/5/2025 5:55pm

Been running it in MXGP all of 2025. I took this pic at Lommel.

IMG 2459 4
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bestmx
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11/5/2025 6:07pm

When I was in the pit at the MXdN I noticed some of the KTM's had those. Maybe Lucas Coenen's? Looked like a damn 2-stroke pipe

Look like this?

IMG 4682 2

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PRM31
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11/5/2025 6:14pm
Brent wrote:
Been running it in MXGP all of 2025. I took this pic at Lommel.

Been running it in MXGP all of 2025. I took this pic at Lommel.

IMG 2459 4

I just want one of those Ti bike stands. 

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11/5/2025 7:02pm
Brent wrote:
Been running it in MXGP all of 2025. I took this pic at Lommel.

Been running it in MXGP all of 2025. I took this pic at Lommel.

IMG 2459 4
PRM31 wrote:

I just want one of those Ti bike stands. 

You can buy from from Ducati for $900. 😳

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kage173
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11/5/2025 7:15pm Edited Date/Time 11/5/2025 7:18pm

I'm surprised it made it through outdoors without getting smashed or a whole punched through ot. Just seems oriented in a way to invite that.

* Am I wrong that the Queen was gone for a while and now posting again? Maybe just me

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11/5/2025 7:19pm
kage173 wrote:
I'm surprised it made it through outdoors without getting smashed or a whole punched through ot. Just seems oriented in a way to invite that.* Am...

I'm surprised it made it through outdoors without getting smashed or a whole punched through ot. Just seems oriented in a way to invite that.

* Am I wrong that the Queen was gone for a while and now posting again? Maybe just me

Have you ever seen a two stroke?

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Not hillbilly
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11/5/2025 8:47pm

Catalytic converters have finally arrived on race bikes!

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BossWool2800
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11/6/2025 3:01am

When I was in the pit at the MXdN I noticed some of the KTM's had those. Maybe Lucas Coenen's? Looked like a damn 2-stroke pipe

bestmx wrote:
Look like this?

Look like this?

IMG 4682 2

😳 Holy Cow lol

FGR01
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11/6/2025 4:34am

Some early design drawings.

Stomach graphic design illustration | Premium Vector

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Steve Austin
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11/6/2025 5:26am

When I was in the pit at the MXdN I noticed some of the KTM's had those. Maybe Lucas Coenen's? Looked like a damn 2-stroke pipe

bestmx wrote:
Look like this?

Look like this?

IMG 4682 2

😳 Holy Cow lol

I'd bet that thing is a bit "pipey" 

bvm111
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11/6/2025 7:01am

they ran them last year it isn’t anything new it’s for the new lower sound levels that FIM are going to and AMA will go to in the future. 

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aeffertz
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11/6/2025 7:03am

I believe that’s what you call a fupa. 

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pummel
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11/6/2025 9:41am Edited Date/Time 11/6/2025 9:43am
AA1OGsOt
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Snapper
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11/6/2025 10:15am

When I was in the pit at the MXdN I noticed some of the KTM's had those. Maybe Lucas Coenen's? Looked like a damn 2-stroke pipe

bestmx wrote:
Look like this?

Look like this?

IMG 4682 2

I'm curious to know what this sounds like...

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11/6/2025 10:21am

When I was in the pit at the MXdN I noticed some of the KTM's had those. Maybe Lucas Coenen's? Looked like a damn 2-stroke pipe

bestmx wrote:
Look like this?

Look like this?

IMG 4682 2

Snapper wrote:

I'm curious to know what this sounds like...

This would be a good idea for a YouTube video, I would like to hear it too, and see dyno comparisons.

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T-Fish
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11/6/2025 11:18am
Brent wrote:
Been running it in MXGP all of 2025. I took this pic at Lommel.

Been running it in MXGP all of 2025. I took this pic at Lommel.

IMG 2459 4
PRM31 wrote:

I just want one of those Ti bike stands. 

kylemenz1 wrote:

You can buy from from Ducati for $900. 😳

Link? I know a buyer! We’ve been trying to find a source for this KTM for a couple of years with no luck. 

11/6/2025 12:04pm
This would be a good idea for a YouTube video, I would like to hear it too, and see dyno comparisons.

This would be a good idea for a YouTube video, I would like to hear it too, and see dyno comparisons.

It will have pathetic low end torque for starters.  Weak mid and top end, and poor throttle response.

KTM put a lot of R&D into that header to avoid it acting like a two-stroke expansion chamber

11/6/2025 1:36pm
PRM31 wrote:

I just want one of those Ti bike stands. 

kylemenz1 wrote:

You can buy from from Ducati for $900. 😳

T-Fish wrote:

Link? I know a buyer! We’ve been trying to find a source for this KTM for a couple of years with no luck. 

https://www.ducati.com/us/en/accessories/ACC013166

Swap the Ducati for KTM graphics 

FGR01
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11/6/2025 4:13pm
PRM31 wrote:

I just want one of those Ti bike stands. 

kylemenz1 wrote:

You can buy from from Ducati for $900. 😳

T-Fish wrote:

Link? I know a buyer! We’ve been trying to find a source for this KTM for a couple of years with no luck. 

11/6/2025 4:50pm
kylemenz1 wrote:

You can buy from from Ducati for $900. 😳

T-Fish wrote:

Link? I know a buyer! We’ve been trying to find a source for this KTM for a couple of years with no luck. 

FGR01 wrote:

Damn!  The Ducati sticker cost $600 more. 

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yak651
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11/7/2025 3:31am Edited Date/Time 11/7/2025 2:56pm

It’s almost like people haven’t looked at a KTM until Eli got on one 😂

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DonM
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11/7/2025 6:29am
yak651 wrote:

It’s almost like people haven’t looked at a KTM until Eli got on one 😂

No shit they've been running this pipe since the last few races of SX and people are now just seeing this as new....

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