What happens if you unplug o2 sensors

[blockpower]

Ok may sound like a daft question but I've been reading threads about o2 sensors and I could do with some clarity please.

on a standard UK bike can you just unplug the o2 sensors? what would happen?

I have read some aftermarket systems don't use them but for standard is it the same?

Confused .com

[Kowalski]

Nothing will happen.

The ECU is aware of it and records it as a fault code internally but there is no light on the dash or anything like that.

[viperclaw]

Originally Posted by Kowalski

Nothing will happen.

The ECU is aware of it and records it as a fault code internally but there is no light on the dash or anything like that.

"nothng" sounds pretty confident.

Just because there is no light on the dash doesn't mean that there isn't a change in the way the bike is running. When one fails or is failing it causes some running issues. Most guys, if not all, that disconnect their O2 sensors are also running some type of fuel managment system (Power Commander V or Bazzaz).

[BSR-1]

I'm just about to cross this bridge myself.
I'm putting a full Graves Ti system on and a PCV.
On my 2009Fz1 I just removed the sensor and all was fine.
I hear that if you don't remove the o2 sensors that the ECU will be constantly fighting to correct the fuel mixture to what it was programmed to while the PCV will be trying to adjust to the fuel map that you're trying to run.

Anybody know anything different?

[Brett64]

For what its worth,,Im about to disconnent my PCV ,re-attach my O2 sensors and put my faith in the stock ECU.
Fitting the PCV seemed like a nice easy mod, but the autotune module is beyond my abilities so I just went with the downloaded map.
Im running a full akra evo system( installed and highly recomended by the dealer) and am experiencing alot of backfiring since installing the PCV.
I think the stock ECU works well with a racing exhaust and a few extra HP are not what's stopping me from being faster.

[skapan]

I know of more than one rider that has installed the full Akro system without adding a PC - they say the bikes run fine after the initial adaptation period. As others have said, a few horsepower here or there may not be noticeable.

[Kowalski]

Originally Posted by viperclaw

"nothng" sounds pretty confident.

Just because there is no light on the dash doesn't mean that there isn't a change in the way the bike is running. When one fails or is failing it causes some running issues. Most guys, if not all, that disconnect their O2 sensors are also running some type of fuel managment system (Power Commander V or Bazzaz).

A faulty sensor is different from an absent one. When you remove the sensors the Lambda loop is deactivated. The Akropovic installation instructions actually tell you to remove them.

After installing a full system I ran my bike for a month or so with the O2 sensors removed before installing a power commander. No problem. Just a wee bit lean.

[BSR-1]

Originally Posted by Kowalski

A faulty sensor is different from an absent one. When you remove the sensors the Lambda loop is deactivated. The Akropovic installation instructions actually tell you to remove them.

After installing a full system I ran my bike for a month or so with the O2 sensors removed before installing a power commander. No problem. Just a wee bit lean.

So the ECU didn't richen the fueling to compensate for the full system?

How much difference with the PC? are you running the "off the shelf" mapping?

[Kowalski]

Originally Posted by BSR-1

So the ECU didn't richen the fueling to compensate for the full system?

How much difference with the PC? are you running the "off the shelf" mapping?

I don't believe this or any other bike is able to adjust fueling for an exhaust change. The o2 sensors are strictly to overcome emission regulations and only operate under the narrow range of conditions dictated by such regulations (eg cold starting, idle and cruising). This is as I understand it at least.

When I first installed the PC I used a map from the Dynojet web site. It was OK. A creamier midrange was the most noticeable improvement.

I Decided to go with an autotune rather than dynotune just out of interest. My bike is a track bike and it is now hitting the limiter on a short straight were it didn't before, I can also pull a gear higher through a particular corner complex so it would seem I have picked up a bit of mid and top end. Unfortunately it hasn't manifested in quicker lap times yet

I still have that bog/surge thing cracking the throttle midcorner. Not everyone seems to pick it up and I am slowly getting used to it but I'd love to now how to eliminate it.

[BSR-1]

Originally Posted by Kowalski

I don't believe this or any other bike is able to adjust fueling for an exhaust change. The o2 sensors are strictly to overcome emission regulations and only operate under the narrow range of conditions dictated by such regulations (eg cold starting, idle and cruising). This is as I understand it at least.

When I first installed the PC I used a map from the Dynojet web site. It was OK. A creamier midrange was the most noticeable improvement.

I Decided to go with an autotune rather than dynotune just out of interest. My bike is a track bike and it is now hitting the limiter on a short straight were it didn't before, I can also pull a gear higher through a particular corner complex so it would seem I have picked up a bit of mid and top end. Unfortunately it hasn't manifested in quicker lap times yet

I still have that bog/surge thing cracking the throttle midcorner. Not everyone seems to pick it up and I am slowly getting used to it but I'd love to now how to eliminate it.

I'd agree with bike ECU not learning and being able to adjust but I've been hearing about how this BMW ECU is supposedly a learning ECU, like in my Camaro.
I'm trying to decide between the autotune or a custom map.
Do you have to spend a lot of time playing with it or do you just install it and forget it?
I've read the instructions but some people say you have to work on it and some don't.

Any additional input is greatly appreciated.