[LAV1000]

Please post your latetst tune, easier for the specialist to see what is happening.
How much ccm is your engine ?

[Hich]

Please post your latetst tune, easier for the specialist to see what is happening.
How much ccm is your engine ?

See attached. Yesterday was late... I wrote 2cyl. but it should be 1.
Physical properties of the engine: 4 stroke, 1 cyl., 1 inj, 200ccm
Tunerstudio: 2-stroke, 1 cyl, 1 inj, 100 ccm
Base pluse width 5.2s. Does that make sense?

Thanks Karsten

[LAV1000]

Not sure about the 100-200ccm setting.
A 100cc 2 stroke needs fuel every crank rotation, a 200cc 4 stroke needs fuel every 2 crank rotations.
Have no idea how speedduino handles this in "Basic Distrubutor" settings.

Then I noticed something in the settings for "Tuning" the vertical axis for TPS are set at 25 ?
Control algorithm is set at TPS.
Did you calibrate TPS ?
So both axis in VE and Spark table should be set to 100.
For the first 10 take some smaller steps, better/easier for of idle to speed and low speed behaviour.
Then there is in VE table "Multiply VE value by MAP ratio" set it to of for now.

Now first start up.
When it starts keep it running, adjust ve table so it keeps running and does have a normal idle when at working temperature.
Now it is time to adjust VE table and maybe spark.
For idle would aim for somewhere between 13-14, idle is mostly a bit rich.

Now you can start tuning the other settings in de "Startup/Idle" part.
Startup > cold engine.

When posting tuning questions alway post the tune (msq) it is related to.
And figure out how to make and post a datalog, they are going to ask for it....
Since there are going to be a lot of msq's, name/code it in a way which works for you.

[Pezi]

Why 100ccm? It doesn't matter whether it's 2-stroke or 4-stroke, the displacement is the same.
What is different between 2-stroke and 4-stroke is that with 2-stroke, EVERY crankshaft revolution is injected once and ignited once.
With 4-stroke, fuel is injected once per crankshaft revolution and ignited at the next revolution.

I would personally leave the displacement as it is for the calculations.

- Displacement: 200ccm
- Injector: xxxccm (depending on what you have)
- Injector Staging: Simultaneous
- Squirts per engine cycle: 1
- Engine Stroke: 2
- Number of cylinders: 1
- Number of injectors: 2

In that case, half of the gasoline you need would be injected at every revolution. That means the right amount once for your entire working cycle.

If that doesn't work, it's because the Speeduino doesn't know how to handle the additional injector. I've never tried anything like that.
Then I would test the following setting.
- Displacement: 200ccm
- Injector: xxxccm / 2 (so half of your injection quantity)
- Injector staging: Simultaneous
- Squirts per engine cycle: 1
- Engine stroke: 2
- Number of cylinders: 1
- Number of injectors: 1

[PSIG]

Why 100ccm? It doesn't matter whether it's 2-stroke or 4-stroke, the displacement is the same.

2S/4S matters to fuel and ignition timing. This is all an experiment, as Speeduino does not respond as-expected with single-cylinder 2S/4S. I would set-up on the bench, and pipe a basic signal into the board, changing settings until a usable pattern develops on the 'scope. @noisymime has run 1-cylinder before, knows the code, and should have some input on this.

Somewhere in here, verify the spark plug HV wire is suppression type, and spark plug is resistor type.

Please review the status of this setup - exactly what is right and wrong with it for function?

[Hich]

Thanks for the good input. Actually I haven't looked at the VE / Spark table values yet. (but probably should have). I have changed this to match 100% TPS now.
Regarding the setup, we have done a bit of fiddeling around with the scope connected to the IGN and INJ outputs and it seems that using
- 200 ccm (as real)
- 2 cyl (instead of 1)
- 128 cc injector flow rate (as specified)
- 4 stroke
- 1 injector
- Wasted spark
delivers at least one ignition per revolution and one injection per revolution, which I think should be ok, as without CAM signal I can't distinguish between the different cycles.

However, we ran out of time with testing and did not get the engine to run, so not yet sure if the fuel amount is ok.

Another a bit tricky issue with this engine may be that the cranking speed ~ 1100 rpm is quite high and Tunerstudio complains when setting this above 1000 rpm, so the cranking settings may not be used. The target idle is given with 1350 rpm.
Current tune attached.