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Wide band O2 sensor and 2 strokes

Posted: Sat Mar 02, 2013 10:27 pm
by KR-RZ350
Can they be used as a tuning tool or is the 2 stroke too dirty to have a "clean" reading for any extended period of time? Where would be the best place to put the sensor? Was thinking of getting one of these LM-2 reader/datalogger.
http://www.innovatemotorsports.com/" onclick="window.open(this.href);return false;

And just saw this.
http://www.iwt.com.au/easitune.htm" onclick="window.open(this.href);return false;

Or is EGT still the best way?

Re: Wide band O2 sensor and 2 strokes

Posted: Sat Mar 02, 2013 10:50 pm
by xkabooomx
From what I understand two strokes foul o2 sensors. I've heard of some "special" o2 sensors for dyno testing but they also are short lived. I use egt's with good results.

Re: Wide band O2 sensor and 2 strokes

Posted: Sun Mar 03, 2013 12:11 am
by steveloomis
What temperatures are considered a safe range, unsafe etc. I have been looking but do not know what to expect when tuning.

Re: Wide band O2 sensor and 2 strokes

Posted: Sun Mar 03, 2013 1:17 am
by xkabooomx
Temps are very subjective, and can vary depending on location from the skirt. You are best to tune using dyno/plug chops and then establish a base line temp. But temps are considered safe below 1200*F Aluminum melts at aprox 1250* but I have personally seen higher temps @ 6" from the skirt with no problems. But my timing is stock 31k and an advanced timing may get a more thorough burn in the combustion chamber @ higher rpm, thus lowering the exhaust temp.

Re: Wide band O2 sensor and 2 strokes

Posted: Sun Mar 03, 2013 7:36 am
by RuZty
Smurph posted some stuff on O2 sensors in his thread on fuel injection,

http://www.rzrd500.com/phpBB3/viewtopic ... t=injected

Re: Wide band O2 sensor and 2 strokes

Posted: Mon Mar 04, 2013 1:43 am
by KR-RZ350
Couple things from reading sled forums

1. WB sensors will last about a season(don't know how many hours that is?)
2. Too much heat will kill the sensor(above 1100f)
3. Will start to read lean as it gets contaminated(some mentioned cleaning with carb cleaner)
4. Innovative recommends placing the sensor in the can(because of heat issues)

Re: Wide band O2 sensor and 2 strokes

Posted: Wed Mar 06, 2013 4:53 pm
by Bngt
Interesting. I have a Zeitronix ready to install. I use one in my Porsche 951 and am very happy, but fourstrokes are different and I would also like to know where to put the sensor. I would expect that putting it early would foul it with fresh gas overflow.
http://www.zeitronix.com/

Re: Wide band O2 sensor and 2 strokes

Posted: Wed Mar 06, 2013 6:46 pm
by r5baker
I am fairly new to this board, but I thought I'd share my experiences. I have tried two different O2 sensor locations on my R5/RD350. The first time I tried it it was in the header section about 8" from the exhaust port outlet on the inner radius of the bend. This seemed to yield decent results for jetting above 4k rpm. Below 4k it seemed to get confused by the pulsing of the flow or the raw unburned fuel/air blowing across it. Years ago this helped me dial in the jets on my VM28's.

Most recently I tried the belly of the pipe on a very different setup. This yielded much more stable results, but I am guessing that due to on pipe/off pipes scavenging it seemed to lie to me at times. It is consistent, but you have to realize when unburned fuel and air moves across it it thinks lean, but it can mean rich. You can also have lean misfire and rich misfire which both can result in lean readings. I had times it was so rich like at the pipe anti-resonance (5500 or so) it misfired which resulted in super lean readings. The most believable area was when on the pipes and even then I had to resort to augmenting the tune by feel and plugs based on previous carb. jetting and O2 readings.

I am still in the process of tuning fuel injection and ignition advance on my R5/RD350 using a crank triggered 60-2 wheel, Electromotive TEC2, WRX injectors, and FZ6R throttle bodies using a MAP/TPS blend method so I had no "jetting" to start with. The WB is quite helpful but you have to understand its limitations especially on a 2-stroke application.

Eric