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Secondary Air System Removal

36368 Views 60 Replies 12 Participants Last post by  gebadop4
Ok as requested here is my attempt at a how to of removing the Secondary Air System on the scrambler.

You want to do this if you have a free flowing exhaust and are experiencing popping and banging from the exhaust under deceleration.

The SAS injects air from the intake filter housing and directly feeds it into the exhaust part of the cylinder head. Due to the high temps and leftover unburnt fuel ignition occurs! According to Ducati this is to smooth out the engine at low rpm and prevent the cat from becoming clogged up.

After the mod the popping was vastly improved and I experienced no rough running or negative conditions in the engine, high or low rpm! Yours may be different but I would say give it a try and if it doesn't work for you then simply reverse the mod.

Time scale 10 - 30 mins depending on skill level
Tools needed 2 x cable ties and smallest Allen key in the supplied toolkit
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You've posted the same thing in 3 places now, so I have to chase you around. :)

That makes sense if it's a valve, but TransNone13 says it's a sensor and it's vacuum operated. Which is it?

In the service manual it's exclusively referred to as a sensor.
No, I was referencing the reed valves. I'm saying cap it or remove it to keep it clean. I might do his resistor trick.
It's a valve. If you unplug it, it won't operate (obviously). The resistor is just there so it doesn't throw an error code.
Did you use a resistor on yours? To do it right with that connector I would want to cut it off then solder it then shrink wrap it, but then that would also not sit well with me.

This is all I did:

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Waiting for it to arrive from the vendor. These things cost pennies, and are widely available.
Of course, I'm not new to this stuff. Radio Shack down the road has them. Did you remove the plug or cut the plug? IF you removed it, did you simply fashion a tool?
I just figured out how to safely remove the plug, it's stupid easy. I'm going to solder in a resistor then shrink wrap it.
If you want, I'll do a quick write up while I do it.
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I'm doing this right now, this is too simple with the specs you shared.
PS Tony, would this trick transfer to the Panigale? I want to remove that as well. I assume if this fails somehow, I will see a check engine light? I hope so, then I can troubleshoot it...
I wish we could edit posts....

Anyway, to revert back to stock simply remove the tack soldering job after cutting off the heat shrink. Then reinsert the plugs into the plastic connector (which I would label), viola!
Yes, should also work with Panigale. If something fails (resistor, wiring, etc) it will throw error code.
Right, but does that trigger a check engine light? I don't have a DDS... Sorry if I misunderstood your answer. And thank you for the info on the Panigale!
I just put on a 67Ω 1/2 W resistor to test. It get's quite hot when active. Too hot to touch if I really work it, but it doesn't fail or anything. It's interesting because you can tell it activates the SAS when you close the throttle. If you blip the throttle quickly (rev-rev-rev-rev-rev) it'll heat up quickly and get hot. As soon as you stop doing that, it cools right off. If you slowly increase revs or hold revs, the resistor stays cool. At least that was my observation. The heat is probably fine since you'd not likely sit and rev like that over and over and over, and the resistor cooled back off quickly.

TransNone13, if you hold your resistor and blip the throttle a bunch, how hot does your resistor get?
I notice it got warm, i held it before I soldered to see if it would fail. That's why I asked about the 'check engine light'. I'll be closely monitoring to in the coming days to ensure it doesn't fail catastrophically. I mean, I bought 5 for like $1.50 so, if it fails I'll look for a solid resistor.

I'll order some of these for the future. Much better resistors:

RSMF12GB47R0 Stackpole Electronics Inc. | RSMF12GB47R0-ND | DigiKey
Did you hook all of your hoses back up, or keep them plugged?
I capped everything, no hoses. I also ordered some flame proof resistors to swap to when they come in for peace of mind.

AnotherHobby, if you want 1 or 2 of those for yourself, I will send you some!
Two would be awesome! Then I can do my brother's Scrambler too. :)
Alright, well I expect them next week. I'll put 2 in an envelope for you. PM me your addy when you get a chance.
If anyone is interested, I have 7 left over, 4 spoken for... so if you'd like 1 PM me with your address and I'll drop one in an envelope.

Redid my SAS bypass with a fireproof, industrial resistor:

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Any reason we are not using 5 watt wire wounds - if heat is a concern ?

No, I'm just more motorcyclist than electrical engineer and this seems to be working.
Just wanted to post back that the resistor ultimately failed, put the valve back on for now. Might want to look into the wire coils...
Crap, I just put it on this morning and didn't see your post until now. :(

Oh well, my hoses are already plugged anyway, so I can just undo it and plug the wires back in.
Run it until it goes and then just put it back on if you feel so inclined. No harm, no foul. Just need something more robust to handle the heat cycles it seems.
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