TOPIC:

For temporary duty, just to check the jetting.

I'm installing it on a bike that seems pretty much jetted spot on:
It starts easily when cold or hot.
Comes off choke very quickly, even in cold weather.
No popping in the exhaust.
Has smooth power all the way through redline.
Has full power in a wide range of temperatures.
The plugs are medium to dark tan.
Tailpipe is dark dark gray to black.

I'm installing it on this bike so I can record what the air/fuel should be at varying throttle/RPM/load conditions on a good jetting. Then I will use this to check other bikes. (Previously, I had a Heathkit EGA that seemed very accurate, but could not be taken on a moving vehicle, so was really only useful for idle.)

So does anyone know what numbers I should expect at WOT, top gear, 5000 to 10000 RPM ?

Lorcan? Steell? You guys still around?
Anyone with a good link to a/f info?

Anywhere between 12.5 - 13.5 /1 is where your bike will make the most power under throttle.(so im told). It should be pretty close to 14.7/1 at 1/8 throttle (for cruising), and at idle. But I like it a little richer to assist cooling...

Remember though, on a multi-cylinder/carb machine, the idle mixture screws are never accurate at "exact turns out settings" theyre peek settings are all slightly different due to small variations in the carb itself.

To get proper readings, a sensor needs to be installed in each exhaust pipe (one at a time is fine), individually for an actual proper reading.

Cheers.

Thanks TeK9iNe, that's about what I've read too.

However, the idle air-screw settings, using the "lean-drop" method almost always comes out to 13.25 on the old EGA. That is what is considered "balanced" and is the target point on the EGA meter for carburetted engines. That's where I get the highest idle and smoothest idle for the widest range of temperatures. For a carburetted bike, that can't adjust for temperatures like fuel injection can, I think 14.7 is way too lean. I know it'll idle at 14.7, but it definitely does not like it. (The EGA does show other taergets for fuel injection and lean-emission vehicles in the 14 range.)

Luckily, I use the TK-22 carbs which are pretty uniform. I've adjusted idle mixtures independently for each cylinder multiple times on multiple bikes and was surprised to find the air-screws almost always ended up within a 1/8 turn of each other, and often within 1/16 turn. I just think those carbs are very precise when clean. I don't think I had as much luck on Mikuni's. (The few Keihin's I've done seem to come out pretty consistent too.)

I also think 13's are too lean under load, based on the old EGA, since opening the throttle gets briefly down near the 11's under load. But I've never been able to sustain a throttle position since I couldn't ride the bike. I've tried to use the brake as a load, but it's too finicky and the disk overheats in about 5 seconds.

Oh well, I I should have it hooked up pretty soon and will report back in case anyone is interested in actual numbers for a normally aspirated, stock motor.

Im in line for the results! or I'm "Inline 4") the results!(air cooled of course

Installed and ready to try, but the weather is not cooperating. In the meantime, I'll post some photos of the setup.

It's not pretty, but it's only temporary and should work ok.

First, let me say, the Kawasaki drill impressed me. The bung requires a 1 inch hole and the Kaw drill was the only one I had with a 1/2 inch chuck. I had my doubts about its chuck and torque, but handled the abuse pretty well. Definitely had to use two hands when the bit grabbed into the rusty header. I figured the chuck would slip, but it gripped the bit just fine.

This is the test mule.
81 KZ550 D gpz. Stock airbox and filter with kerker 4-to-1 with quieter street baffle.

o2 sensor screwed into weld-in bung. The weld was ugly because I don't have much experience with the flux-core mig and it was tough to get the gun to it. I can't take the header off because I believe the header bolts are going to snap when removed. (The bike sat out in weather a long time before I bought it. I've tested the bolts and they are ready to snap.)

The header is diposable since it was so rusty anyway.

Here some ugly wiring. This bike is still running the original prototype for the HEI ignition.

That's the Innovate LC-1 O2 processor on the right side with the aluminum band holding it to the frame. It has a lot of serial communication cable I don't need on the bike. It's for the option to setup on a PC or hooking up to other LC-1 units.

I just slapped the calibrate button and led status/error indicator in line with the cabling.

Note the shopping cart seat-belt strapping.

Mounted the gauge in foam. It's for a car so I figured it may not like the vibration. I may have gone overboard on the mount, but like I said, it's just for testing.

Here's the old Heathkit EGA with its tailpipe sampler.