Running with O2 sensors unplugged

Anybody have experience of running a 750, single TB / Twin O2 sensor model, with the O2 sensors
unplugged . I am thinking in terms of thousands of miles rather than just up the road and back .
I know this subject has been raised in the past , but would like to hear the pros and cons / comments
from riders that have tried it .

What I can say is I’ve been working on a lambda correction device for mine, and if I temporarily disconnect the feedback signal from the sensors the default fueling is rich (constant high level output from both O2 sensors).
As I don’t have a means of measuring AFR I can’t say how rich, but I’d guess the mixture is in the right ball park to ensure no major problems if a lambda sensor should fail.

I think the only risk of running disconnected is ruining the cats, or worse having the cats overheat and turn blue.


Disconnecting O2 sensors forces open-loop fuelling. All that means is the ECU has to rely on its default fuelling map. I’d be very surprised if that damages the cat I mean what happens if a sensor innocently fails? Doesn’t really make sense.

Thanks for the replys chaps , my thoughts were about if one sensor packs up a long way
from home , disconnecting both as a get home bodge , but didnt want to do any permanent
damage .
Changing the subject Mike H , have you aquired a Ural ?
I have visited David Angels shop a couple of times , such a refreshing change from the
usual bike dealerships . I am somehow drawn to the Urals rugged simplicity .

Whatever makes you think that? :laughing:

Yes I have, AND I bought from him.

‘Fact yesterday he invited me over to a MZ owners’ camp do he was attending, on t’other side of Horncastle, whiled away a pleasant afternoon. He is indeed a most knowledgable bloke about Urals must be said, and a damn fine chap to boot.

Yes I agree Mike. Just thought I’d mention the risk because the default map is definately on the rich side (O2 sensor outputs a solid ‘high’ when running open loop).