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Discussion Starter #1
Does anyone know when the exhaust valve actually closes?

I was playing around with it and it appears to be full open at idle, I manually changed the position at idle and it got significantly quieter making me think it is full open at idle. I changed the ride modes thinking maybe it would quite it down in urban mode, but it made no difference. I'm sure it is also full open at WOT. So does it close somewhere it the middle of the rev range?
 

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I think it's closed around 4000 rpm. But I disabled my valve by removing cable and servo, no errors are reported on the monster 1200.
 

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Ducati says it helps low-end torque. Not sure I believe it but I have never seen proof one way or the other.
 

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It's closes right around the rpm sound testing is done for standards as that's its only use.
Considering how loud the bike is stock compared to what my HD was stock I would believe they put this in as a way around the noise bylaws, especially in Europe. The most disappointing day of my life was the day the sales guy at the Harley dealer started my new Sportster up before they got the V&H exhaust in for it; I asked him if I was supposed to ride it or sew with it!:p
 

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Its for low end torque. Buell's pioneered it and has been copied by a few manufactures (along w/ centralized mass, engines as stressed members, underslung exhaust etc)

On a XB series Buell you can comletely feel the difference in torque between a functioning exhaust valve and one that has been wired open or changed out for a straight through "race" muffler.

*edit to add* it does quiet the exhaust on a Buell at idle as it directs the gasses through a 2nd chamber. Not sure thats the case w/ the Ducati's
 

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Discussion Starter #8
Its for low end torque. Buell's pioneered it and has been copied by a few manufactures (along w/ centralized mass, engines as stressed members, underslung exhaust etc)

On a XB series Buell you can comletely feel the difference in torque between a functioning exhaust valve and one that has been wired open or changed out for a straight through "race" muffler.

*edit to add* it does quiet the exhaust on a Buell at idle as it directs the gasses through a 2nd chamber. Not sure thats the case w/ the Ducati's
On the Monster it is definitely open at idle. It would be interesting to see before and after dyno runs although who changes just the exhaust valved without anything else... I suppose you can always disconnect the cable and do a seat of the pants feel...
 

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Its for low end torque. Buell's pioneered it and has been copied by a few manufactures (along w/ centralized mass, engines as stressed members, underslung exhaust etc)

On a XB series Buell you can comletely feel the difference in torque between a functioning exhaust valve and one that has been wired open or changed out for a straight through "race" muffler.

*edit to add* it does quiet the exhaust on a Buell at idle as it directs the gasses through a 2nd chamber. Not sure thats the case w/ the Ducati's
No it is not. It's for noise regulation. Don't believe me, get a dyno, run it, undo the valve, run it again and see what you get. If anything you'll see a tiny improvement in power and smoothness with it undone.

As EEE pointed out, it's wide open at idle. How is that going to help with scavenging for low end torque? If you do investigate, I have a funny feeling you'll find it closes up pretty suddenly around 4,800 rpm which makes zero sense for any sort of performance gain.

As for Buell and pioneering....oooooooookay.
 

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Hi guys,
I think that everyone that owns a recent Ducati SHOULD disable or remove the exhaust valve.
It frees up the engine on low revs.
Put the bike on the side stand and stand on it's right.
Rev it slowly and at the same time look at the side of the valve, you can watch it moving and understand how it messes up with the engine.
This feeling that the engine does not want to rev freely past idle at light throttle opening, the feeling of the sound disappearing at some revs...Its all the valve's doing! Unplug the thing go for a ride and if not convinced, plug it back in.
Actually we, monster 1200 821 and Hyper 821 owners, are very fortuned as unplugging it won't produce a warning light on the dash. We don't need a Duc.EE to eliminate the light. Maybe Ducati realized that the majority of owners are disabling it and made life easier on us...maybe!!!
 

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How to unplug it and test for yourself.
The motor is located in the battery bay under the swing arm. Undo the two aft screws (not the middle ones) and flip open the compartment door. Secure the battery through the left small opening with a small screwdriver.
Find the only connector plug in there and unplug it. The cable is quite short from one side and the plug wont come out for you to work on it. I grabbed the male connector with a pair of pointed pliers and used a small electrical screwdriver in the side slid to open the catch and push them apart. Not very easy if you are inverted on your back, have a flash light on your mouth, and wear reading glasses!!
I tried to put some electrical tape for insulation but soon gave up. Tie rap the plugs so they won't rattle around.
 

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As EEE pointed out, it's wide open at idle. How is that going to help with scavenging for low end torque? .

Its open at idle so it doesnt choke the engine. If it was only for "noise reduction" designing a better can would have been more cost efficient. ****, adding one inch of length would quiet it more than a fluctuating valve.
 

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Its open at idle so it doesnt choke the engine. If it was only for "noise reduction" designing a better can would have been more cost efficient. ****, adding one inch of length would quiet it more than a fluctuating valve.
Yep. Cost is the driver here...for sure.

Here's an example of Ducati and "cost efficient". I can't imagine why they didn't do that for the 1200.



Guess they could go the route below but then it'd be totally quiet, not just at the rpm where testing is done...which isn't the goal, the goal is to make an exhaust that is loud but passes noise tests. Oh yeah, and it's fugly.



but hey, I have virtually no Buell experience at all and have been told first hand the purpose of the Ducati valve....what do I know?
 

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Actually we, monster 1200 821 and Hyper 821 owners, are very fortuned as unplugging it won't produce a warning light on the dash. We don't need a Duc.EE to eliminate the light. Maybe Ducati realized that the majority of owners are disabling it and made life easier on us...maybe!!!
May still trigger a code that doesn't show on the dash.
 

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Reading up about the exhaust valves accross different model ducati and it seems on some bikes the valve only operates in neautral purely to pass sound db requirements. Once in gear and riding the valve stays open. Has it been confirmed by someone if this is the same for the 1200 / 821 monster
 

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Reading up about the exhaust valves accross different model ducati and it seems on some bikes the valve only operates in neautral purely to pass sound db requirements. Once in gear and riding the valve stays open. Has it been confirmed by someone if this is the same for the 1200 / 821 monster
This is not true.
 

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Sonic duck, so I can unplug the plug in the battery compartment and it will not throw a code that only the dealer can pickup? Or switch to an alternative trim map due to this? As the company that sells the ee module say the 1200/821 wont show a fault code on the dash but they will show a code when scanned by ducati. From reading some have said their bike has shown the code when scanned by ducati.
Regards some other model ducati exhaust valve only closing whilst in neautral there had been some owners hook a cam up facing the valve modual while riding and once underway it never moved again. This was not a monster though and im not saying the monster works that way im simply asking if it had been checked.

Is there a chance of running lean if I disconnect the plug since the stock fuel map is already lean?
 

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Discussion Starter #19
Hi guys,
I think that everyone that owns a recent Ducati SHOULD disable or remove the exhaust valve.
It frees up the engine on low revs.
Put the bike on the side stand and stand on it's right.
Rev it slowly and at the same time look at the side of the valve, you can watch it moving and understand how it messes up with the engine.
This feeling that the engine does not want to rev freely past idle at light throttle opening, the feeling of the sound disappearing at some revs...Its all the valve's doing! Unplug the thing go for a ride and if not convinced, plug it back in.
Actually we, monster 1200 821 and Hyper 821 owners, are very fortuned as unplugging it won't produce a warning light on the dash. We don't need a Duc.EE to eliminate the light. Maybe Ducati realized that the majority of owners are disabling it and made life easier on us...maybe!!!
Why not just disconnect the cable and let it think its actuating the valve?
 

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I disconnected the the servo mechanically and electrically in preparation for installing full termis I had on order. Between the disco and termi arrival, I took the bike in to the dealer (GP in San Diego) for the first service. Within minutes of them having the bike, they came out and asked why I had it disconnected and that it was throwing a code.


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