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Thanks man, you've been a huge help!
Secondary Air System Removal
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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 it's unlikely that you'd rev like that over and over and over. The resistor cooled back down quickly, so I think in normal use it'll be fine.
TransNone13, if you hold your resistor and blip the throttle a bunch, how hot does your resistor get?
TransNone13, if you hold your resistor and blip the throttle a bunch, how hot does your resistor get?
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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
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Did you hook all of your hoses back up, or keep them plugged?
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I capped everything, no hoses. I also ordered some flame proof resistors to swap to when they come in for peace of mind.
http://www.mouser.com/ds/2/447/Leaded-R_FRM_2011-12977.pdf
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AnotherHobby, if you want 1 or 2 of those for yourself, I will send you some!
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Two would be awesome! Then I can do my brother's Scrambler too.
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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.Two would be awesome! Then I can do my brother's Scrambler too.
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Here is my method, very easy and totally reversible...
http://www.ducatiscramblerforum.com...how-diy/17545-how-disable-sai.html#post211521
http://www.ducatiscramblerforum.com...how-diy/17545-how-disable-sai.html#post211521
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599 Posts
Update...
Just discovered that if you disable the O2 sensors (via Rexxer or some other means) you a can leave the SAI completely intact. The solenoid valve will not operate without feedback from the lambdas, and remains closed.
Sent from my iPad using Tapatalk
Just discovered that if you disable the O2 sensors (via Rexxer or some other means) you a can leave the SAI completely intact. The solenoid valve will not operate without feedback from the lambdas, and remains closed.
Sent from my iPad using Tapatalk
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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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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 ?
Cheers
Cheers
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No, I'm just more motorcyclist than electrical engineer and this seems to be working.
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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...
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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.
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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.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.
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129 Posts
Did you ever find a suitable resistor?
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Did anyone else try again to put the resistor to trick the ECU?
I did a test on my Monster 797 (same 800cc engine as the Scrambler), I put a 1kOhm resistor to reduce the electrical current (and the heat).
I found that:
1) Just by doing Ignition ON (Key ON), the voltage difference between the resistor is 0V, it means that no current flows inside (i.e. the ECU does not turn ON the valve). MIL lamp is OFF.
2) Cranking the engine (engine cold condition), the ECU still does not turn ON the valve. MIL lamp is still OFF.
3) After riding few km (~2 km), the engine failure lamp (MIL lamp) suddenly turned ON, and the idle became rough. I stopped the bike.
4) I read the DTCs using a ELM327, and DTC P0413 was "Confirmed DTC". The meaning of this DTC is "Secondary Air Injection System Switching Valve A - Circuit Open".
My conclusion is that the resistor value of 1kOhm is too big, and therefore when the ECU turns ON the valve (transistor closes the circuit to GND and therefore the current flows in the resistor), the voltage detected by the ECU feedback diagnosis is not in the right range, so the ECU detects "Open Circuit". Definitely, a smaller resistor has to be used: you were successful with a 50 Ohm, while I got an error with 1000 Ohm, so I wonder where the limit is located. I will try with 50 Ohm resistor, however I am concerned by the heating, so I bought "10 W resistors" on Amazon.
By the way, someone in this forum said that putting the resistor is worthless, because anyway this valve is "normally Open" and therefore if not powered, the valve stays open and exhaust constantly communicates with the intake (except for the reed valve in series, which stops back flow). So, the resistor does not solve the popping issue. Is this true?
I did a test on my Monster 797 (same 800cc engine as the Scrambler), I put a 1kOhm resistor to reduce the electrical current (and the heat).
I found that:
1) Just by doing Ignition ON (Key ON), the voltage difference between the resistor is 0V, it means that no current flows inside (i.e. the ECU does not turn ON the valve). MIL lamp is OFF.
2) Cranking the engine (engine cold condition), the ECU still does not turn ON the valve. MIL lamp is still OFF.
3) After riding few km (~2 km), the engine failure lamp (MIL lamp) suddenly turned ON, and the idle became rough. I stopped the bike.
4) I read the DTCs using a ELM327, and DTC P0413 was "Confirmed DTC". The meaning of this DTC is "Secondary Air Injection System Switching Valve A - Circuit Open".
My conclusion is that the resistor value of 1kOhm is too big, and therefore when the ECU turns ON the valve (transistor closes the circuit to GND and therefore the current flows in the resistor), the voltage detected by the ECU feedback diagnosis is not in the right range, so the ECU detects "Open Circuit". Definitely, a smaller resistor has to be used: you were successful with a 50 Ohm, while I got an error with 1000 Ohm, so I wonder where the limit is located. I will try with 50 Ohm resistor, however I am concerned by the heating, so I bought "10 W resistors" on Amazon.
By the way, someone in this forum said that putting the resistor is worthless, because anyway this valve is "normally Open" and therefore if not powered, the valve stays open and exhaust constantly communicates with the intake (except for the reed valve in series, which stops back flow). So, the resistor does not solve the popping issue. Is this true?
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I think that 50 Ohm 5W should be OK.
Because, even with a battery voltage of 15V, the heat dissipated in the resistor would be 15*15/50 = 4.5W which is below the limit.
I tried with a 1000 Ohm resistor but while running I got an error, the ECU detected "Open Circuit" (DTC code P0413), so I think that it's too big.
However, someone in this forum said that the "resistor mod" does not help because anyway the valve is "normally open", i.e. when disconnecting the power it remains open, and therefore the flow of fresh air from air box to exhaust is permanent, therefore completely f**k**g up the lambda control.
Not sure if this is true or not, anyone knows?
Because, even with a battery voltage of 15V, the heat dissipated in the resistor would be 15*15/50 = 4.5W which is below the limit.
I tried with a 1000 Ohm resistor but while running I got an error, the ECU detected "Open Circuit" (DTC code P0413), so I think that it's too big.
However, someone in this forum said that the "resistor mod" does not help because anyway the valve is "normally open", i.e. when disconnecting the power it remains open, and therefore the flow of fresh air from air box to exhaust is permanent, therefore completely f**k**g up the lambda control.
Not sure if this is true or not, anyone knows?
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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.
Hi
The two tubes removed which have been blanked off with the rubber caps.
What did you do with the tubes are those blanked off as well, what are they connected to?
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