Where can I get a PDQ O2 Sensor bypass on line?

[Onedownfiveup]

Topic says it all. Where they at?

[PaulBerg]

Its actually a 'Dynojet O2 Sensor Eliminator' Part #76423006. You can order one from any Dynojet dealer.



PDQ is a tuning shop here in the UK (www.pdq1.co.uk (http://www.pdq1.co.uk)). They will sell you one but do not have an online facility.



Paul

[Frank.B]

You can purchase these online at http://www.triumphtiger-online.co.uk/ (http://www.triumphtiger-online.co.uk/)

I would imagine that they would ship these to the USA.

[JRO]

First, I would find out how these things are supposed to work.  



The 02 sensor sends a signal to the bike's brain, which adjusts mixture and interval, updated thousands of times a second.  If you spoof the bike's computer with a constant signal from the 02 sensor, then how is it adjusting?  It isn't.



I've heard pros and cons about these 02 sensor eliminators; I used to be interested in using one, my own self.  But the tech info and reviews I've read all seem to indicate that they don't really work; can't work.  There's no data flow to adjust your fuel injection with; just a constant signal.  Bike will be lean or rich, all the time.

[PaulBerg]

I talked to a helpful chap at Dynojet in the UK (Dynoject make the O2 Eliminator Kit) before I bought the kit and he told me the following:



The Triumph's ECU Leaning Function only works when:

- throttle position is below something like 30% open

- revs are below something like 3000

( i can't remember the exact figures)

this is so it leans the mixture at the throttle/rev/speed/ required to achieve the drive-by speeds specified by our friendly regulators to measure emissions. The ECU tries to lean the mixture to BELOW the ideal fuel/air ratio based on readings fom the sensor. Once revs and throttle position exceed the cut-off points, the ECU stops auto leaning (i.e. goes out of closed loop) and instead just implements the fuel map.



By fitting the kit, the ECU is fooled into thinking it has achieved its emissions target and stops the auto-leaning function.



O2 Sensors which transmit slightly higher ful/air ratio readings than actual (due to manufacturing tolerances) result in jerkier bikes. Conversely, O2 sensors which transmit slightly lower readings result in smoother bikes. This explains why some owners have more of a problem than others - its that finely balanced. It also means that in theory, you could solve the problem by buying 20 sensors and finding the one with the 'best' output.



Dynojet originally developed the O2 eliminator because they could not sell PowerCommanders without it on some bikes: the auto-leaning function was counteracting the Power Commnder - every time the the PC tried to increase fuelling (in the low rev/ low rpm range of the auto leaning function) the ECU would counteract it. This meant that Dynojet could not offer a product which had perfect fuelling (no flat spots etc) for all bikes at all revs and throttle openings. So they devised the O2 sensor bypass for several bikes, not just Triumphs.



They also sell O2 eliminator kits to people who fit after market exhaust headers which don't have a hole to plug in the O2 sensor (e.g. the speed triple customising brigade).



That's what the friendly Dynojet man told me anyway.....and it seems to make sense.



For myself, all I know is this kit (plus loosening the chain) transformed a jerky, snatchy, irritating '05 bike into a smooth performer which I will be keeping for a long time. I have not noticed any increase in fuel consumption. I would have sold the bike without this kit.

[Chris Canning]

I also bought and after some miles took it off,being an 01 it takes all of 2 seconds to do,BUT i wouldn't poo poo them,it make the bike different,it may suite you,it may not,the only sure way to know is to try one.



Might even try it again,after all,hardly going to break the bank cost all of £17/18!!!.



Although for people with later Tigers more of a pain to fit,were as on the early ones,it's a case of pull up, plug in and of you go,a direction comparison in the space of a few seconds.

[Onedownfiveup]

Yeah, the problem that I have is with the surging below around 4000 rpm's. It's annoying and I hate clutching to get rid of it. I have read alot about these bypass kits (they are essentially a resistor?) and thought I would try fitting one. Something in the bias or in the indication inputs for the fuel mapping is not right or suffers calibration deviation error at times. Somethimes the bike is more snatchy than others.



When I mountain ride I never have the surging problem. More evidence to support that the sensors that feed the ECU or the bias are not configured correctly.

[ghostbiker955i]

I use one on my 05 model tiger. tried it to stop the low end surging problem that was starting to bug me. it did help that but i lost a lot of the Burble noise it makes when i back off now and i realy liked that :) so i will remove it next time im under the tank/airbox. but it did do its job.