Bonneville America Forums Forums Technical Forums Exhaust Effects of removing O2 sensors - 2012 Speedy

What is the effect of removing the O2 sensors and installing the Dynoject O2 eliminators? I would turn off the sensors in TuneECU as well (or do I need to?).

http://www.motorcycle-superstore.com...sor-eliminator

Advice, Pros and Cons would be appreciated.

You must turn off the sensors in the ECU if you are going to remove them. There is nothing gained in removing the sensors themselves except the looks. There are gains in turning them off though, you get smoother low speed handling ... The transition response between closed throttle and low throttle is smoother because the AI is not being activated.

The link you posted doesn't work, but I searched MSS and I don't see the the Dynojet Oxygen Sensor Eliminators are relevant to our bikes. Why would you use a Powercommander on an EFI bike? Just use TuneECU to modify your tune directly in the ECU.

All you need to remove the sensors is a couple of plugs with the right pipe (tapered) thread.

On my Rocket III, if you remove the O2 sensor but don't install the Dynojet O2 Senor Eliminator plug, the ECU will throw an error even if you disable the O2 sensor in TuneECU.

I'm curious to know if the Speedy will do the same thing.

Definitely not installing a Powercommander on the Speedy.

The MSS page said "use with Dynojet Powercommander."

It is possible that they changed something in the ECU in recent years to cause an engine check light. Mine is an 09.

Where do you install the Dynojet? Are we looking at the same thing? The O2 sensors are in your headers. Because the MSS page I found has an oblong plastic (presumably) electrical) device. It is not a plug.

Just to be clear, you're not really talking about removing the AI solenoid under the tank? Because removing that after turning off the O2 sensors in the ECU (without replacing the solenoid with the correct resistor) will throw a check light .

No, sir. I'll speak from my experience on the Rocket. When you remove the O2 sensor from the exhaust and follow the lead to under the right side cover (you have to move the ECU as well) there is a connector. When you unplug the connector, there is a O2 Sensor Eliminator Plug that you have to plug in on the bike side. My guess is that this 1/2 inch long plug fools the ECU into thinking that the O2 sensor is still there.

For the Speedy, I would assume that there are 2 of them, one for each O2 sensor. I should be getting the headers back from the coater tomorrow and some bung plugs are on their way. Once everything is fitted, I'll just unplug the O2 sensors and see if the ECU throws an error. I'll then disable the O2 sensor in TuneECU and upload the map.

Again, no Powercommander involved here. Not thinking about one. Don't want one. Don't need one. Dynojet just happens to also make the little O2 Sensor Eliminator Plug which is what I'm looking for.

The eliminator plug looks something like this:

Oh OK. The web page for the dynojet said it goes with the Powercommander unit so that got me confused. I think your assessment that it fools the ECU would be correct. In that case I think you wouldn't want to turn off the O2 in the ECU.

I removed the AI system, turned off the O2 in the ECU and left the O2 sensors in the headers for a while. This was fine but the AI solenoid would chatter as it tried to adjust the AF mix on closed throttle (but of course it did nothing because there was no AI plumbing). This got annoying so I replaced the solenoid with a resistor (can't remember the resistance) and then it was quiet. Finally I removed the O2 sensors and replaced them with plugs with the appropriate thread. Nothing was required to connect to the O2 sensor leads. I just taped them to seal for moisture.

That's why I suspect the dynoject connector you are talking about may only be required IF THE O2 IS NOT TURNED OFF in the ECU.