Anyone have an opinion on this?

http://*******.com/22sqeg

It's an A/F-ratio gauge that can be simply connected to the signal wire of your O2 sensor and I assume a 12v power source. If you have a PCIII like I do, the O2 sensors are not being used, so it seems by doing some simple wiring could have A/F ratio visible while you're riding. There is a conversion that must be done, as the gauge reads in millivolts, but it looks usable.

The seller says the display is not waterproof, but that he's sold these to many bikers without complaint. I think you could mount it somewhere on the fairing where water would not be an issue.

 

The existing O2 sensor with a meter has some tuning value depending on how you are trying to tune. The narrow band O2 sensor is capable of indicating if youonly three things, if youare at 14.7:1 A/F, more rich or more lean then that. It is not capable of telling uswhat A/F we are at outside of this 14.7 ratio like a wide band O2 sensor can. For adding a guage, the NBO2 sensor puts out a 0-1V signal with .45V representing a 14.7 A/F. Because the voltageoscillates many times per second between .2 to .8 volts when at 14.7, most guages aredampened so the indication is stabalizedto indicate14.7 when there. Many NBO2 guages come with their own O2 sensor that has 3 or 4 wires meaning that it is a better O2 that has a heater circuit for quicker readings after engine startup.

So, it has some tuning valueespecially if you are trying to achieve a 14.7 ratio foridle or cruising, I have our bike set upeven more lean for cruising. Another value is that it can be a diagnostics tool in that if you are having a fuel issue causing a misfire, it may tell you ifit is being caused by a too lean or too rich condition. NBO2 systems are of limited value for wide open throttle tuning because they cannot indicate what A/F you are at if you are shooting for around 12.8 to 13.2, like previously stated, it will just indicate that you are more rich then 14.7 which has some value but that's not enough.

Now if you really want to do it right and you do your own tuning, the best money that you'll ever spend for your bike is a wide band A/F monitoring system. You simply replace your existing O2(s) with the supplied O2(s). Most kits are single WBO2 systems but there is a new kit out, I can't remember who, that is now offering a dual WBO2 kit which would be great for your application. I'll look up who that is if anyone is interested.

Here is an example of a single WBO2kit that I have used. http://www.aempower.com/ViewCategory.aspx?CategoryID=67

Autometer and several other companies offer NBO2 guagesetups.