Using Wideband O2 Sensor for Carb Tuning

I have a Innovate LM-1 wideband kit that I used to tune my hot rod. I'm wondering if I could use it to tune my bike. I'm planning on welding a bung for the O-2 sensor just after the primary tubes. I will use the battery tender connection to power up the unit. The LM-1 would be tie wrapped to the handlebars. I'd be going for 14 to 1 idle and part throttle cruise and about 12.8 to WOT. I may go a bit richer than these numbers since the engine is air cooled. What do you think?

Here's a topic from the KZ650.Info site. He used a spare header pipe to mount the sensor.
note: on his 650 the #1 & #4 exhaust pipes are removable (ie, not welded to the mufflers).

KZ650.info --- Lambda sensor. Your ultimate weapon. by Z650Spirit . I think you have to register & log-in to see the topic.

Cant hurt to try it out and at least check what the numbers are before and after a good tune up
Dave

14 will probably be too lean for idle. On an average temperature day you will want to shoot for about 12 ish, otherwise cold days will be way too lean and you'll need choke much longer.

For part throttle crusing, I shoot for 13.5 to 14. That's up to about 3/16 throttle or so. Above that I try to keep it in the 12.5 to 13 range. (That is for steady state cruising where the RPMs are no longer climbing.)

WOT AFR's will swing as RPMs climb. You want the AFR to sweep through the power range as the RPMs sweep up to redline. So I find best power when the AFR sweeps from about 11 at the beginning of the power band to about 13 or 13.5 at redline.

And, of course, temperature will affect the AFRs. Everything will start to report richer as the bike and air temp get hotter. I try to tune on the 70 to 80 degree days.

Also, this is all for non-CV carbs.

Didn't OMR have a long thread about this a while back?

Thanks for the info. I'm running BS34 carbs. Would there be a difference in tuning these compared to the mechanical carbs?

I have a wego and love it. I tune different carbs on my bike all the time. Its also interesting how temperature changes the readings. I try and set it at 13 give a take couple decimals. Doesn't always work that way in the whole range. Some carbs are different then others on how they respond. You can always get the idle right on. I struggle with part openings and cruising. Some carbs will be spot on with just a little load and then when it "coasts" a little its way off. I think Id have to be more into changing emulsion tubes and I just want to change jets and needle heights.

loneagle wrote: Thanks for the info. I'm running BS34 carbs. Would there be a difference in tuning these compared to the mechanical carbs?

I haven't used a wideband on CV carbs yet.

I assume idle would be the same strategy.
I think the main difference with the CV's is that it doesn't let you open the throttle too fast. With mechanical slide carbs, when you open the throttle too fast, the AFR goes very rich. This effect will be reduced with CV carbs. So my initial strategy would be to set the lower level, steady throttle positions the same way as with mechanical carbs. That is, I hold the throttle steady and let the bike climb to whatever speed it can attain in top gear. I usually try to hold steady at 1/16th intervals up to about 1/4. In that range I try to aim for the upper 13's to maybe the lower 14's for the AFR. Above 1/4 or so, I try to get closer to 13 to 13.5. Then when I get above 1/2, the bike will be going too fast to really hold steady for any long period of time. So I will use acceleration tests in lower gears and just observe the swing up to redline. I aim for low 13's as the final AFR at redline, but make sure most of the swing is in the 12 to 12.5 range.

With some combos I find there may be a slight rich position in the 1/4 to 3/8 area. As with anything, there are tradeoffs you make in place to fix up another. But usually you can get a decent compromise worked out to handle a wide range of temps.

Thanks for the great info. Now, I'm excited to get the wide band hooked up and go for a ride.

At first the readings will seem crazy. It's only after you start to see the pattern that it all makes sense. That's why I like the analog gauge. I don't have to focus on it to get the gist if what is happening. I'll see if I can find a link to one of my threads with a video.

The thread is so old the photos are gone, but the links to the videos should still work on page 2.

www.kzrider.com/forum/3-carburetor/30748...d-o2-sensor?start=20

That's some great information. Thanks for sharing!