Removal of air injection system

Has anybody removed or disconnected/plugged the air injection system at the front of the cylinder heads? I see a plug and play removal kit for the monster 821 but not sure it will work on hyper. I can fashion my own plates but don't know if it will throw codes or cause poor running, ecu corrections, etc. Anybody done this?

What does this system do or attempt to do?

Is this to do with carbon filter, evap system fitted to some bikes with strict emission rules

This is to stop popping on agressive throttle inputs. It originally is ment to pump atmosphere air into the exhaust at certain times to help meet emissions regulations. Supposedly it helps performance if you have an aftermarket exhaust with no catalytic converter. How to disable Ducati Secondary Air System - Monocilindro Blog: Motorcycles and Electronics

So this is for the air cooled engines, not the LC ones, so doesn't apply to the 821

For almost all bikes. Not just ducati. There are kits for the 821, 939 and 950. Here is another link with some info.

Sweet thanks for those links!

It doesn't affect performance or rideability at all. I blocked mine off while datalogging O2 values by simply plugging the lines to the cylinder head reed valves. You can stick a marble in there or anything to plug it up. Some people remove it to simplify the look of the bike. It will make it pollute more that's about it haha.

I have a full system, and it pops a lot on decel. My only concern was that my AFR was off. Don't mind the noise so much. These tap in near the injector assemblies?

Couldnt the deceleration pop break the O2 sensors? Everything I see about the O2 sensors(especially in these bikes) say that they are very delicate. Also, if we were to stop pushing air into the exhaust, couldnt it change the values that the O2 sensors are seeing and affect the tune? The video says exactly that, block it when tuning with aftermarket tuner(you mentioned you did that as well) to get accurate reading and better tuning. Better tuning = better performance? I only know what I have seen in the other links which is why i said "supposedly helps with performance" but an accurate tune will definitely help with performance? I have never done the plates in any bike. In fact, I'm using the Kuksul08 tune slightly modified on my 821.

That's where the RB Evo shines. It actually uses O2 input to help adjust AFR (in AUTOTUNE mode). Most tuners I've worked with on cars in the past just ignore/ block the O2 input, which is why you normally cut and plug them or bypass.

gatdammit said:

I have a full system, and it pops a lot on decel. My only concern was that my AFR was off. Don't mind the noise so much. These tap in near the injector assemblies?

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Popping isn't really a bad thing. It's just a lean mixture in the pipes and helps fully combust the fuel. Some people like the pops haha.

Araitim said:

Couldnt the deceleration pop break the O2 sensors? Everything I see about the O2 sensors(especially in these bikes) say that they are very delicate. Also, if we were to stop pushing air into the exhaust, couldnt it change the values that the O2 sensors are seeing and affect the tune? The video says exactly that, block it when tuning with aftermarket tuner(you mentioned you did that as well) to get accurate reading and better tuning. Better tuning = better performance? I only know what I have seen in the other links which is why i said "supposedly helps with performance" but an accurate tune will definitely help with performance? I have never done the plates in any bike. In fact, I'm using the Kuksul08 tune slightly modified on my 821.

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I don't think so. O2 sensors are damaged by sudden temperature changes like going hot to cold or being doused in gas. It can thermally shock the ceramic element.

I believe the stock system is designed to account for the added air when making adjustments to correction map. I don't know too much about that though. What I do know is that if you use a wideband O2 you must block off the air injection or it will skew the readings. The stock system is really quite dumb and only tells the computer if it's at 14.7:1 or not.

I just installed the AIS secondary air blocking plates. Good kit and not expensive. While the plates could be easily machined/ repurposed, the included spoofer plug for the ECU lead and airbox plug save you some time and trips to the hardware store. The hardware itself is very nice aluminum with high-grade mounting bits.

Regarding why this and not just plugging the lines as Kuksul notes, I had damaged the T-junction for this system that hangs off the bottom of the airbox from repeated bashing from R/R the airbox. Plus, big fan of removing unnecessary junk, especially if emissions related. Those lines are a PITA to situate (for me) when R/R the airbox so was happy to get rid of them.

NOTE: Installation is much more involved on our twin than the simple I-4 videos on YT. The forward cylinder may require down pipe removal (mine was already off), or at least O2 plug removal. For the rear cylinder plate, I had to pull all the standard engine access stuff - tank, airbox, battery, ECU - plus the air recirculation system that runs to top of rear cylinder. It's the hard plastic pipe about 1" in diameter that runs from the rear of airbox to top of rear cylinder. I also had to remove the mail fitting that this pipe mates to, which has 3 tiny hex bolts that you don't want to lose and hopefully aren't very tight as they would strip very easily. If it can be stripped, I'll probably do it. It's a curse I've lived with my entire life of wrenching.

I would have an extractor set handy. I stripped a bolt on both OEM ports that the plates replace, even using a sturdy hex wrench adapter. Would not recommend a basic allen key as it will probably snap the key or strip the bolt if you have more than a couple thousand miles on the clock. These are located at very high temp sites and the bolts are practically welded in.

I also just installed this kit. 3 of the bolts were seized and needed some persuasion but they all came out without snapping. It took far longer than expected and the crank case vent valve needed to be pulled(which also had a seized bolt). In the end I don't have any more exhaust pop than before . The only thing I noticed is that the sparkplugs have less carbon on them. I know this because I pulled the plugs thinking my new plugs would arrive in time but they didn't so I put the area in and old plugs back in and rode for another clue hundred miles.

I won't be able to op test for probably weeks as I need a new vertical down pipe. This was one fix of many to correct really poor running, lack of power, **** idle, awful cold start...probably mostly related to the giant holes I found in my header. I'd want more than just this mod to pull the bike apart but I was already stripping it for a number of issues.

So you noticed nothing? Do you have a tuner? I'm just hoping to get back to healthy/ smooth. Haven't had that in a very long time.

I have a feeling that PAIR systems have a lot to do with discoloration/corrosion of stainless headers on modern bikes, due to the extra heat of combustion within the pipes. I blanked mine off the front pot of the Suzy 1k-engined Cagiva Raptor after spending a lot of money getting the headers polished. That bike has no O2 sensors and a much less sophisticated injection system, of course. It made no difference to running, and I think the pipe stays a bit brighter between cleans.

Nick

gatdammit said:

I won't be able to op test for probably weeks as I need a new vertical down pipe. This was one fix of many to correct really poor running, lack of power, **** idle, awful cold start...probably mostly related to the giant holes I found in my header. I'd want more than just this mod to pull the bike apart but I was already stripping it for a number of issues.

So you noticed nothing? Do you have a tuner? I'm just hoping to get back to healthy/ smooth. Haven't had that in a very long time.

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I have a RB Evo tuner. I was expecting some popping from the exhaust but for some reason my bike has never done that. Usually less carbon build up is due to a leaner condition. I asked the question a year or so ago(you might remember it) about how accurate the piggyback tuners are at reading the O2 sensors if they are getting air fresh dumped on them with the pair system. I'm curious if removing the pair system just made the autotune run more exact which cleaned up the carbon on the plugs. The bike still runs strong with it removed. I did pick up an increasing sputter while holding a constant speed under 5k rpm. I dug into the throtle sending unit which I have read was recalled at some point(mine has the old part number on it but Ducati Detroit says the recall was done) . The magnet on the throtle tube itsself is snapped in half so I ordered a new one. They are dragging their feet sending it from Ducati but you are no stranger to long wait times for pretty much anything you order so I feel bad mentioning that it is going to take an extra week or 2 for me. I'm still riding the bike. I did add more fuel to the horizontal cylinder under 5k rpm and that helped but I'm thinking it's the throtle causing the most issue. This sputter is also why I recently replaced the fuel pump. Next was going to be injectors and throtlebodies but I think the tube will sort it out.

After this job, the only thing left causing my CEL is the TPS. How do you locate/ inspect the magnet on the throttle?
Interesting note: That 2nd gear-8K rpm misfire I've had for years vanished just before this downing. I always thought it was injection or sensor related but could be the TPS.

gatdammit said:

After this job, the only thing left causing my CEL is the TPS. How do you locate/ inspect the magnet on the throttle?
Interesting note: That 2nd gear-8K rpm misfire I've had for years vanished just before this downing. I always thought it was injection or sensor related but could be the TPS.

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It is the grey strip that is attached to the white piece that is connected to the thrtle tube. If you pull apart the throtle housing and slide the tube/grip off the bars you will see it. It's like 1mm thick, 1/2in wide and follows the curve of the throtle tube. It's held in only by a tab that is pressed in place. There isnt much room for it to fall out of place but my thought is that it could be vibrating in there causing issues. I'm not sure what the adjustment was with the revised unit but we will find out soon. It is on the outside edge of this pic. You can't see it in this pic. I was just showing someone else the throtle spacer so they snis the only pic that gives an idea where the magnet is

And the reference/ pickup is in the switch gear housing for that grip?