Anyone used the NGK A/F meter to tune an older carb'd VFR?

Air Fuel Ratio Gauge for measuring air fuel ratio by NGK. The Powerdex NGK AFX Air Fuel Ratio Monitor.

I'm thinking about picking one up to tune both my VFR and my wife's HawkGT. I'd also use it to get a sense of how changing the spacers in my Supertrapps change the A/F ratios.

MCN reviewed it in their last issue, and used it to tune a project bike they've been blueprinting. They raved about it. Of course, they also have their own dyno to use it with, too.

 

No I haven't, but i can tell you you must plug the air injection if its a california bike ,, or it will show lean and be all over the map

 

Thanks for the tip on the air injection. It's not a problem my particular bike has, but I hadn't considered it's impact.

 

I bought the Holley Air fuel mixture ratio instrument .
I had to weld the bung in the exhaust that holds the sensor.

The ratio mixture device I bought was for carbs.

It does work. It showed me that the mixture was lean all the way from 1/4 throttle and up.
I talked to Factory pro in San Rafael Ca. and the tech told me that the device will just get you in the ball park. But it was a start. I ended up putting two shims under each needle and substantially improved the performance and throttle response of my VF1000R. I removed the air fuel ratio meter when I was finished testing because the sensor is large and blocks the exhaust flow.
I also found out the VF1000R will take any Mainjet from 125 all the way up to 150.
I am at sea level too. I went with 128's mains and a #40 idle jet, and my fuel mileage is still good. Two .030 shims under stock needles. burrs removed from the shims and measure them to make sure they are all the same.

During this testing I also checked the spark plugs for color.
I have a digital temp guage also.

Oh one more thing... I have just a foam element over the air intake screen and the exhausts are all 30 inches long from the exhaust port to the mufflers
The mufflers have no fiberglass, but there is a washer in each end that restricts the flow.

 

having looked at the FactoryPro website, I've got a fair bit of respect for them. They appear to be no-nonsense "what really works" types. As an engineer, I fully respect the notion that a dyno shouldn't have any "fudge factors" built into it. It's measuring HP, so it's measuring HP. And I'm certain that if I spent the money on a dyno tune on one of their dynos, I'd be very, very happy with the results. I also could buy a new bike for how much that would cost around here in dyno time + mechanic time to swap jets. And to buy a dyno myself... nah, I'll spend 1/10th the money on a gauge that will get me in the ballpark, IF it's actually worth it vs. the butt dyno and trying to do a plug chop (which is very difficult given the mountainous terrain I live in).

 

I have called factory pro twice and ordered jets twice. When i called them they were very helpful and polite. I could tell from my past experience as a dealership mechanic that they knew what they were talking about. Techs not salesmen.