Wideband Tuning 150cc TaoTao By JoeyBee (Read 4,275 times)

[JoeyBee]

For the past 2 weeks I have been trying to fine tune a new carburetor for my TaoTao Powermax. It was running great but I was getting tired of constantly making slight adjustments to the A/F mixture screw then riding and making speed runs.  I also wanted some detailed numbers of how my engine was running.  So I decided to pony-up the cash for a wideband air/fuel sensor kit from Amazon.  With a holiday promotion code, $120 to my door was a steal.

The installation was very easy.  Only hard part was finding a buddy with a welder.  To all the new members, the tuning guide by Alleyoop was perfect for idle (13.2 - 13.5).  My WOT is hovering around 12.6 - 12.9, so I'm going to try a #115 main jet next to bring that down.

I installed the gauge inside the glove compartment to maintain a "stock" appearance.

 

This was the farthest place I could place the sensor.  So far surface temperature of the pipe have reached 250F, but that's only 10 minutes of running on a very cold Texas day.

[Bashan]

Very nice, thanks for posting! I'm sure you'll get more questions about the installation and it's operation. I in fact have a few but I'm too tired, I'll post them tomorrow. Rich

[dmartin95]

Jan 7, 2015 21:54:35 GMT -6 JoeyBee said:

For the past 2 weeks I have been trying to fine tune a new carburetor for my TaoTao Powermax. It was running great but I was getting tired of constantly making slight adjustments to the A/F mixture screw then riding and making speed runs.  I also wanted some detailed numbers of how my engine was running.  So I decided to pony-up the cash for a wideband air/fuel sensor kit from Amazon.  With a holiday promotion code, $120 to my door was a steal.

The installation was very easy.  Only hard part was finding a buddy with a welder.  To all the new members, the tuning guide by Alleyoop was perfect for idle (13.2 - 13.5).  My WOT is hovering around 12.6 - 12.9, so I'm going to try a #115 main jet next to bring that down.

You may find the following video useful.


 

After the 12 minute mark he goes into detail about his O2 sensor, the reading and where it should be. It's the Best GY6 carb video I have came across.

[JoeyBee]

dmartin95

Thanks for the video. I have not seen that one yet.

[JoeyBee]

I'm not sure what type of unit of measurement he is using. I am going by A/F ratio (12.0 - 14.00). .045 is not even on the lambda scale. He did a very good job explaining when each jet is used, but very poorly on the wideband tuning.

I have been using a much better chart which even factors in the mandated 10% ethanol addition.

[JoeyBee]

I forgot the link if anybody else is interested in air/fuel ratios.

www.hotrod.com/how-to/engine/1307-wideband-oxygen-sensor/#__federated=1

[cyborg]

Nice work Bee,,and thanks for the link too,,,,mixture is very important,,,this helps to get the maximum performance from these tiny engines,,,,they need every scrap of power they can get

[JoeyBee]

Jan 10, 2015 10:05:37 GMT -6 cyborg said:

Nice work Bee,,and thanks for the link too,,,,mixture is very important,,,this helps to get the maximum performance from these tiny engines,,,,they need every scrap of power they can get

Your welcome for the link. I agree with this engines they need all the help they can get. For me I was also worried about running the engine too hot causing damage by a lean condition. That added engine protection was well work the money.

One tip I have for anyone thinking about a similar installation is to throughly check all the connection points of the exhaust when welding on the sensor bung connection. When I was checking the entire length of my exhaust for leaks one was located where the factory made a connection after the first bend. Now I will have to remove the exhaust again and fix the factory's poor workmanship.

It is not too bad, but according to the manufacturer's technical material this will slightly screw the readings during engine idling towards being leaning. When the engine is under load the reading should not be affected.

[dmartin95]

Jan 9, 2015 4:03:01 GMT -6 JoeyBee said:

dmartin95

Thanks for the video. I have not seen that one yet.

You're welcome. 

I'm not sure what type of unit of measurement he is using. I am going by A/F ratio (12.0 - 14.00). .045 is not even on the lambda scale.

He is not using a "Kit" that comes with a A/F gauge. The unit of measurement is volts, or rather, millivolts (mv). His "gauge" is actually a volt meter.... Actually, he's using a Millivolt meter.

The O2 sensor is a very simple device. It only has 4 wires. Positive and negative for the O2 output reading, pos and neg for the built in heater core.  

The O2 output wire sends out a signal in between 0~1volt (anything under a volt goes into the Millivolts). Now, .450mv is when you're at a near perfect (2% exhausted oxygen) output.... Go lower than .450 you're heading towards lean. Go above, you start going into the rich side. 

Had you asked me this question a month ago, I wouldn't have the slightest idea how to answer you. However, my wife bought me an Ecotrons EFI for Christmas and it comes with an O2 sensor. I have been researching how each component works and the O2 sensor is a critical component and I needed to learn how it works in conjuncture with my scooters ECM... Ecotrons doesn't include a gauge for the O2 sensor, so I have to learn how to read the voltages, not a gauge...

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By the way, that kit you purchased you got at a steal! That was a nice price and your install looks great. Good Job!