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Discussion Starter · #1 ·
Anyone disabled their exhaust valve yet? I have a small electronic eliminator off my 848 that imitates the motor so that it does not throw up an error code, but have not tried it in the SS yet.
I assume that the valve is spring loaded open.
 

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What are the benefits of removing this?
I thought it would be fully open when needed and as your not removing the valve the restrictions are still there.
 

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The valve is operational at low revs for the city and traffic etc.. keeps emissions down. The valve is in the cat box and the motor under the horizontal cylinder on the right side. To be honest removing it will not present any great improvement in torque or hp. It does not limit performance but limits pollution.
With the full race system I only got 1.4hp and 1nm extra so I really cannot see the butterfly being in the open position aiding any performance improvement. Not being a pessimist, its simply my experience with the SS.
 

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So, coming from having no clue about these valves, how does it limit emissions?
 

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Hmm, I found this:

Exhaust valves and servo motors explained

Admittedly, it's trying to sell something, but explanation seems reasonable. Seems more like a noise thing, than emissions?

I'll probably continue to be part of the silent majority, and leave the bike stock...However I have other bikes that I've monkeyed with over the years, so it's not wrong to play, if you like that kind of thing!
 
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Discussion Starter · #7 ·
It as nothing to do with emissions, but is all about noise tests. It does not only operate at low revs but also at high. I have videos of mine on both the 848 and the SS operating throughout the rev range.
One good reason to disable it is that they seize, ask on any Multistrada forum, and can then throw error messages on the dash and be costly to rectify.
I have removed the motor and the ugly cable that hangs below the engine, and wire locked the valve open.
 

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2017 Ducati Supersport, 2015 Ducati Scrambler Classic, 1994 Ducati 907ie
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It as nothing to do with emissions, but is all about noise tests. It does not only operate at low revs but also at high. I have videos of mine on both the 848 and the SS operating throughout the rev range.
One good reason to disable it is that they seize, ask on any Multistrada forum, and can then throw error messages on the dash and be costly to rectify.
I have removed the motor and the ugly cable that hangs below the engine, and wire locked the valve open.
As the previous owner of a 1200 Multi for the last 5 years I can vouch for all Fred says. The exhaust valves sooner or later will seize, reducing power and showing an error on the dash. If it is seriously broken the only way of restoring it is replacing the entire cat.
I will leave mine until the bike is out of warranty and then look at disabling it. On the MTS this can be done by removing the cable from the valve and fitting a small spring on the end of the cable so that the servo motor thinks the butterfly is working, but sooner or later the cable will seize so it would be better to eliminate the servo motor altogether.
 

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I am so happy with all the emission controls that are going to save the planet. I'm not already feeling the difference.
From what i have read in this forum, you should be glad you don't live in california and have to work within their vehicles emission laws. Euro 4 is presently on our SS, the euro 5 regulation cuts euro 4 by half. Wont be long before the cat is bigger than the engine
 

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It's common on many bikes for the valve or cable to gradually get stiff and then the servo motor fails. Can be expensive as I've found out in the past.
 

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It's common on many bikes for the valve or cable to gradually get stiff and then the servo motor fails. Can be expensive as I've found out in the past.
Hmmm, anyone have a recommended lubrication or maintenance procedure other than disable or remove it to prevent failure?
 

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Spray a lubricant in spray in the girdle of the cable between servo-motor and exhaust valve, and also on the mechanism of rotation on the valve. We can make nothing for the servo-motor in himself.
 

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The valve is operational at low revs for the city and traffic etc.. keeps emissions down. The valve is in the cat box and the motor under the horizontal cylinder on the right side. To be honest removing it will not present any great improvement in torque or hp. It does not limit performance but limits pollution.
With the full race system I only got 1.4hp and 1nm extra so I really cannot see the butterfly being in the open position aiding any performance improvement. Not being a pessimist, its simply my experience with the SS.

Is this thing removed eliminated when they fit the full Akra exhaust system ?
 

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Is this thing removed eliminated when they fit the full Akra exhaust system ?
Yes, it is removed and put in a box with the coffin cat...and other bits n pieces.
Ducati service centre plug in the upmap dongle supplied with the exhaust, and they connect their DDS and disable the exhaust valve motor, and remove it. The actual valve is in the cat.
 
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