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FG1
04-01-09, 10:11 PM
I have a K8 with the sensor just near the cutting area for adding an after market can.
I also have the already cut pipework from a K6 which doesn't have the sensor.
So, what I want to know is......
How important is the sensor, if I disconnect it will it fook my bike up ?
Would drilling a hole and welding a suitable nut on my K6 pipework to accept the sensor be a suitable solution ?
OR.....
Would I be better off just cutting my K8 pipework and using the already fitted sensor.

TSM
04-01-09, 10:31 PM
I have a K8 with the sensor just near the cutting area for adding an after market can.
I also have the already cut pipework from a K6 which doesn't have the sensor.
So, what I want to know is......
How important is the sensor, if I disconnect it will it fook my bike up ?
Would drilling a hole and welding a suitable nut on my K6 pipework to accept the sensor be a suitable solution ?
OR.....
Would I be better off just cutting my K8 pipework and using the already fitted sensor.

we have very little info on the K8 and its diffrences, but yes if it has it there and its disconnected or gives back the wrong info to the ECU then it will be problematic.
Its ok to drill hole and put sensor back in, weald has to be gas tight.
The other possability is to find out the standard resistance of the sensor and put a resistor across the conector and you can remove the sensor, but my opinion is that it should be there.

Nobbylad
05-01-09, 02:40 PM
I have a K8 with the sensor just near the cutting area for adding an after market can.
I also have the already cut pipework from a K6 which doesn't have the sensor.
So, what I want to know is......
How important is the sensor, if I disconnect it will it fook my bike up ?
Would drilling a hole and welding a suitable nut on my K6 pipework to accept the sensor be a suitable solution ?
OR.....
Would I be better off just cutting my K8 pipework and using the already fitted sensor.

If you do cut the K8 pipe, make sure you cut it 55mm or more from the weld as there is an insert in the pipe, kind of like a honeycomb centre that you'd have to cut through if you go any closer. Not sure what it's there for, but probably some noise/flow control or summat!

Hope you enjoy the new bike!

embee
05-01-09, 04:41 PM
I don't know aything about a K8 specifically, but as general comments, that "honeycomb" will be a catalyst, I'd guess a metallic substrate rather than ceramic. That's where the clean up of the nasty regulated pollutants goes on, CO, HC and NOx.

Lambda sensors work a little bit like a battery, one side of the business end is exposed to exhaust gas, the other side of it is exposed to atmosphere. If it has free oxygen on both sides (i.e. the exhaust is "lean") there's no output, if the exhaust has no free oxygen ("rich") there is an output. The switching from hi-lo happens very close to a true stoichiometric air/fuel ratio (i.e. the chemically correct ratio for the fuel).

The ECU uses this switching "feedback" to keep the mixture pretty well at stoich during most of the light load running (usually ignores the feedback and goes "open loop" at high load and maybe at a threshold high speed too).

Removing the sensor will almost certainly cause some sort of running problem, and if the ECU doesn't see the response it expects you would normally get a "check engine" lamp come up. The ECU will default to some sort of "limp-home" mode usually.

Dangerous Dave
05-01-09, 05:23 PM
If you are fitting a slip-on I would keep the sensor (see TSM's post above), but for a full system I would dump it.

Sid Squid
05-01-09, 05:26 PM
I'd leave it connected if at all possible, even with a full system - as Embee quite rightly says it only affects mixtures at idle/tiny loads anyway, so there's no benefit in not having it.

Nobbylad
05-01-09, 09:59 PM
I don't know aything about a K8 specifically, but as general comments, that "honeycomb" will be a catalyst, I'd guess a metallic substrate rather than ceramic. That's where the clean up of the nasty regulated pollutants goes on, CO, HC and NOx.

Lambda sensors work a little bit like a battery, one side of the business end is exposed to exhaust gas, the other side of it is exposed to atmosphere. If it has free oxygen on both sides (i.e. the exhaust is "lean") there's no output, if the exhaust has no free oxygen ("rich") there is an output. The switching from hi-lo happens very close to a true stoichiometric air/fuel ratio (i.e. the chemically correct ratio for the fuel).

The ECU uses this switching "feedback" to keep the mixture pretty well at stoich during most of the light load running (usually ignores the feedback and goes "open loop" at high load and maybe at a threshold high speed too).

Removing the sensor will almost certainly cause some sort of running problem, and if the ECU doesn't see the response it expects you would normally get a "check engine" lamp come up. The ECU will default to some sort of "limp-home" mode usually.

Thanks embee...that's really useful :thumleft: