[Rednaxs60]

Read through your past, we are on the same page, just stated differently.

I see a gap in concept, and I hope you will give me an opportunity to offer a different mind-set of the concepts.

… I went up/down the VE table cell values and had to lean out the cell numbers, not much but noticeable.

Why did it need leaning-out? What was your goal? Why did you think it was rich of something? What something is that? Why is important to the concept.
No worries on this one, fumes in garage, and eyes burning.

… I know the fueling is "rich", so my options are to reduce the amount of fuel - VE table cell changes (maybe complementary change in timing - retard), or give the fuel charge more time to burn (advanced timing).

Yes, to a goal. I see a small but significant gap in concept. It says OR instead of AND. If you adjust one you adjust the other, each + and - to find optimal values with data, because fuel and spark work as a team. What optimal values? That depends on the goals at that point of operation. Adjust your mindset from rich or lean to optimized. "I know it's rich lean not optimal, and I need to find the fuel and timing values it is optimal."
Always about relationships, to get the engine tune as smooth as possible and MAP lowest. Lambda/AFR readings observed for possible table changes.

Will pick a set of parameters (engine RPM, Gearing, Speed), adjust VE first, then timing for that specific set of parameters before moving on.

Yes! But adjust to what? Adjust to the goal for that point of operation. We can have many goals, but one goal is primary at a specific point.

For most general applications, the goal for initial tuning is peak efficiency for either torque (power) or economy. Pick which one fits there, and tune (using data) to achieve that goal, at that point. There are other goals and efficiencies, but we're not there yet, and set our base tune on those two as a baseline. Modify for other purposes after the tune foundation is built.

In the generic example table below, note areas 2 and 3 have max torque as the typical goal, and the other areas do not require max torque and so are targeted for minimum fuel consumption. Some efficiency is always maximized, and if it's not torque we need, then it's economy to gain. We tune with data to find max torque fueling and timing to support it, or max economy fueling and timing to support it, for every point on the tables.

You pick which goes where for your purposes, goals, preferences, etc. Print a copy of your table, and mark or highlight every cell for which goal each cell will have - torque or economy. Tune each area for that chosen goal. That's job one. Crawl before you walk, and walk before you run.

Cim526-L-1[1].jpg

Take note of the lambda/AFR readings and if reasonable, adjust AFR table.

Reasonable for what? You see where we're going with this at every point. To repeat, we never tune or adjust to an AFR. Get "adjust AFR" out of your head. We only tune to the chosen peak efficiency, then read what AFR that peak efficiency produces. The result of our tuning to peak values. Enter that value into the AFR Table , in order to maintain that best value you found in the future. Repeat in a new area. Connect the dots.

Right there with you. Not tuning to lambda/AFR, but these readings corroborated with spark plugs, mean a lot. If the plugs start to come out closer to what I expect, fuel and timing is getting to where it should be.

[PSIG]

OK Earnest, perhaps someone else should try to get the basic concept laid-out, as I seem to be failing. There is something in prior training or alternative internet sources that is blocking me from relaying this concept for you. Or, I suck at describing simple concepts.

If the plugs start to come out closer to what I expect, fuel and timing is getting to where it should be.[/i][/b]

There is no "start to" or "getting to". That is lengthy and inaccurate. What it does tell us is that it is not optimal. Your first mission is to find what is optimal at one specific point in the tune. Not sort-of, not better-than, but directly find absolute optimal or best.

You do this with your lawn mower, turning the jet needle from too rich to too lean and set it to the best between the two, using data (rpm, tone, cutting speed, whatever you can use for data). Done in 30 seconds. So is this. Pick a spot on the tables and find peak data. Optimal torque or economy data, as-appropriate. Done. Not closer - perfect. Move to the next area and repeat. Blend between the tuned spots and you have your base tune.

How do we do this again? . . .

Always about relationships, to get the engine tune as smooth as possible and MAP lowest.

Yes, or best accel time, or leanest without surge or partial misfire, or other data showing peak efficiency for whatever mode you're in (torque or minimum fuel consumption). Then ignition to maximize that fuel setting, typically targeting peak performance or minimum MAP.

Right there with you. Not tuning to lambda/AFR, but these readings corroborated with spark plugs, mean a lot.

They do, but only to confirm to you it's not right, and the data has already confirmed that. Use the data and find what is right. Not just getting there — exactly right, the first try. Do this next and it's pretty quick. Get it done on your next tuning day, so you can move on to other tune settings and improvements.

[Rednaxs60]

@PSIG - we are on the same page, just explaining it differently.

Did a road trial this afternoon. Good progress. I've come to a realization that you cannot be too timid with changes, especially when doing it with starts and stops. Keeping track of the MAP reading and engine RPM for the VE table cell adjustments is not the easiest on a bike. If the reason for VE table changes happened in the same area of MAP/RPM more than a couple of times, timing was added. Didn't have time to pay attention to the lambda/AFR gauge readings today. You can feel issues very soon after making changes on a motorcycle.

As I mention, progress. Haven't looked at the data log yet, but have viewed the plugs. Colour is much better:

Road trial plugs .JPG (91.25 KiB) Viewed 702 times

The plugs that are black/sooted are from the other day. The plugs that have better colour are from today. Will be out tomorrow for another road trial. See how many areas I can hit for VE and/or timing adjustment.

Tweaked the coil dwell before the road trial, upped the dwell time from 1.5 ms to 1.7 ms. May have helped, but will investigate coil dwell to get the best out of these COP units I can.

Datalog and tune:

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[Rednaxs60]

Sat down last night with a coffee and some fresh baked peanut butter cookies, and reviewed the data log from the days riding. Will pay more attention to warmup tuning - it's not bad, but for now it's to concentrate on road riding.

Noticed an interesting trend using rpm/s as the primary indicator. There are wild swings in this parameter, but in areas that I have not paid attention to for tuning. Where the VE table cell values have been adjusted, this parameter appears fairly stable. Will start to adjust the VE table cell values to stabilize this parameter in the affected area.

When I was looking at the data log in MLV, did a VE analysis, lambda table not set up as of yet, but wanted to know what MLV might determine for VE table cell values. The VE analysis indicated that the areas of the VE table that have not been adjusted yet need adjustment, should have VE table cell values to decreased. The range is between 2000 and 3600 RPM and engine load of 80 to 40 kPa.

As mentioned, notice the spark plugs are fairly clean, unlike what I would expect. Did some research into this and find that this is quite common. Spark plugs are innocuous parts that we really don't spend a lot of time worrying about. Without getting into a long dissertation on what I found out, spark plugs can be used to provide an indication of fuel mixture, engine timing and heat range. Another tool in the tool box to use. Going to destroy a couple of spark plugs and see what I have been missing. This will be done before the next road trial.

Went and read the Wiki again for the Nth time regarding tuning and the VE table. This page indicates that "The values in this table represent a percentage of the Required Fuel amount that will be injected when the engine is at a given speed/load point." I have been grappling with the VE table cell values concept for a while. This statement has me thinking that if the VE table cell value for a given engine load and RPM is say 40, this means that the amount of fuel required at this engine load and RPM is 40% of the RF value setting in Engine Constraints in conjunction with all the other parameters used to determine fuel injector PW. A value of 75 is 75% of the RF value, and so on. In other words the greater the need for a more fuel rich environment to protect the engine, the higher the number. It has been posted that the higher the number, the leaner the burn, and vice versa. If this were the case, with a VE table cell value is 75, then the fuel required would be 25% of the RF value in Engine Constraints. My observations are that the lower the number, the leaner the burn because less fuel is injected. This is how I will progress.

On to more road trials.

[LPG2CV]

Possibly, the higher the AFR value, the leaner the burn.

[Rednaxs60]

@LPG2CV - thanks for the comment. Will be doing a "seat of the pants" adjustment for this VE table adjustment because most of the engine operation in this area is due to deceleration, then coming out and going to areas that are better tuned. The AFR table cell value adjustments will be an interesting experiment. Weather supposed to improve starting tomorrow. Look forward to getting back out there.

[PSIG]

@PSIG - we are on the same page, just explaining it differently.

Just to be clear — we are not on the same page at all. Several of your comments since my last post confirm this. As I am ineffective in assistance, I'll sit back from here. Sincerely though, best of luck with your "tuning".

[Rednaxs60]

Today's road trial logs attached. Timing is too advanced, will work on this. Redid the ignition table into a wedge table.

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[Rednaxs60]

Another successful road trial. Had made up my mind from the last road trial to concentrate on ignition timing, and coil dwell. Coil dwell does affect the engine fuelling, and changes are being done slowly. The ignition table was made into a wedge table and retarded 2 points before today's trial. The ignition table was retarded today, and the engine seems to like the change. The engine tune is not perfect but coming into focus.

Bought an inexpensive LCR meter for the coil dwell.

This is the latest data logs:

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[JHolland]

Bought an inexpensive LCR meter for the coil dwell.

LCR meters aren't very good for determining the characteristics of larger windings like coils, injectors or bigger solenoids, the output signal is very low power and won't properly energize the coil so you won't get any flux energy in the core and, in the case of an ignition coil, very little coupling to the output winding. You may get a reading of the right magnitude if you're lucky; if you're measuring inductance then try placing a 100 Ohm resistor is series - low resistance coils will just short out the meter and produce a spurious reading.
The correct way to determine inductance and rise times is to measure the current rise time using a scope and then calculate the inductance. Remember the resistance of the coil will change a lot over temperature so do that at normal operating temperature.