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Discussion Starter · #1 ·
Stock exhaust, flap mechanism maintenance...

As has been discussed on the Forum, if the cable and/or exhaust flap valve freezes, it will generate an error on the dash. It happens sometimes, probably more frequently for bikes ridden in the rain often.

I’ve just examined mine and the cable moves freely and the flap mechanism freely rotates, but there was some mud in there around parts of the valve that I cleaned out.

This assembly can be accessed easily by removing a small cover secured by three screws.

Anyone else doing this work on a preventative basis, especially as many of us who purchased the bike are now out of warranty?

Are you using any lube on the valve and/or cable? What type?
 

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2017 Ducati Supersport, 2015 Ducati Scrambler Classic, 1994 Ducati 907ie
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No need. I've a Termi fitted with the upmap. But if I still had the OEM exhaust I'd remove the cable and replace the motor with a servo eliminator. The valve defaults to the open position so maintenance no longer necessary :)
 

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I've read conflicting info regarding this external exhaust valve. In most applications it's meant to add back pressure to enhance torque at lower rpms. But I've also read that it's strictly for sound volume and has no influence towards performance.
 

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I'd be curious if it has a performance implication. On most car servo exhausts, it's purely for sound. But there you usually have long pipes so a little additional back pressure has little implication. With our exhaust so close to the cylinder - who knows! If anyone is maintaining their's please post pics too.
 

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When the MIL light came on at the start of this season, I lubed the wire with some PTFE spray/grease. No issues since. There was no crud on the mechanism itself but I did rotate it a bit back and forth, to make sure it moved freely. Possibly it was slightly stuck at first but not a large degree if so.

Has anyone ever had the valve get stuck completely?
 

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I'd be curious if it has a performance implication. On most car servo exhausts, it's purely for sound. But there you usually have long pipes so a little additional back pressure has little implication. With our exhaust so close to the cylinder - who knows! If anyone is maintaining their's please post pics too.
Hard to say but if it really had a noticeable performance effect, chances are that you’d see more valves like that in motorcycle racing, or in aftermarket systems. The fact that that’s not happening makes me think it’s stricly noise related.
 

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Discussion Starter · #7 ·
Yeah, if it breaks, will replace with a servo eliminator. But it only take a few minutes to maintain, so prolly less time than replacing with eliminator.

Also agree, it’s just for sound compliance regulations...no perf impact. The stock exhaust is amazingly efficient.

I just quickly cleaned the flap mechanism and cable, but will go back in to lube it, and will take pics next time. Very simple job. Remove three screws, pop the cover, clean and lube, replace lid and screws. (Careful with the screws.)

I also took the opportunity to buff the cover with Autosol metal polish to get rid of dirt, tar and other accumulated marks and crap on the cover. Looks like new now after two years of year round use.
 

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Usually most reasons they get stuck is when there is moisture causing corrosion and seizing. Just allow the exhaust system to dry up after washing or complete avoid getting water in the exhaust system at all.
Also allow longer trips so moisture does not build up in the exhaust from warming up the engine.
Lubricating will be almost useless as the exhaust will get so hot that any lubricant will burn off.
Also use full throttle more often to allow the flap to be opened up. The best way to keep corrosion and seizing is to use it.
 

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Usually most reasons they get stuck is when there is moisture causing corrosion and seizing. Just allow the exhaust system to dry up after washing or complete avoid getting water in the exhaust system at all.
Also allow longer trips so moisture does not build up in the exhaust from warming up the engine.
Lubricating will be almost useless as the exhaust will get so hot that any lubricant will burn off.
Also use full throttle more often to allow the flap to be opened up. The best way to keep corrosion and seizing is to use it.
Re: lubing, would agree for the mechanism on the exhaust but there’s definitely a point to lubing the wire from time to time.
 

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Re: lubing, would agree for the mechanism on the exhaust but there’s definitely a point to lubing the wire from time to time.
I have found the sane. Valve is bit the problem, but the cable leasing to it from the servo. I have had the cable seized twice in a years time.

Now I finally cured it permanently with Healtech servo eliminator. I had the cel light on for the first ride, but it hasn't come back after after a few restarts. Seems to work well. Servo is now off the bike, exhaust will be when the Termi gets hete Next week. :)
 

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Discussion Starter · #11 ·
I have found the sane. Valve is bit the problem, but the cable leasing to it from the servo. I have had the cable seized twice in a years time.

Now I finally cured it permanently with Healtech servo eliminator. I had the cel light on for the first ride, but it hasn't come back after after a few restarts. Seems to work well. Servo is now off the bike, exhaust will be when the Termi gets hete Next week. :)
Twice...interesting. Do you often ride in the rain?
 

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Discussion Starter · #12 ·
In addition to a general cleaning, planning next to squirt a little of this Silicone - Teflon stuff into the cable sheath end to hopefully prevent seizing.

 

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After the winter layup, both the valve and cable were seized. I used a teflon spray on the valve and a cable lube in a syringe at the actuator end of the cable. 5,000mls later everything is free and smooth.
 

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Discussion Starter · #16 ·
Image one - carefully remove those three screws to remove cover. I had just cleaned the cover the other day, but 95 F on fresh asphalt, well, you know...

Image two - I had already cleaned the mud and crap off the inside too. What you see here is just the residual.

Image three - after a quick spray of the Silicone/Teflon spray.

Image four - clean up and polish with Autosol.

Image five - ready to ride. Hopefully good for another 12,000 miles and/or couple of years.

Careful with those three screws, they can be easily stripped or broken. Little WD on the screws and fasteners, and careful alignment, then np.
 

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I'm still interested in butchering a standard exhaust to remove the cat but keep the same appearance to keep the local plod happy. Any one willing to sacrifice a disused one for a very nominal price in OZ?
 

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I'm still interested in butchering a standard exhaust to remove the cat but keep the same appearance to keep the local plod happy. Any one willing to sacrifice a disused one for a very nominal price in OZ?
There was a guy on here who attempted that and it’s not that easy apparently. If I remember right, he only managed to butcher up the cat but not really removing much of it, and he even cut up a part of the double skinned cover to get better access.
 

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Thank you Ed K! I had no idea that was even there until this thread started. Seems a good thing to regularly maintain.

Appreciate the pics and walk through!
 

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Checked mine out recently, lower bolts rusted in place. Had to cut the underside one out! Worth checking Guys - 2 in the underside of the fairing rusted too but not checked them yet! I’m in South Wales, UK and don’t ride in the rain much!! Was amazed how rusted they were!
 
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