Digiplex Ignition - Running on 1 cyl

[Weg]

My Calli 1100 is one of the last carbed units with Digiplex 2S electronic ignition.
It's only running on the left cylinder.
PHF 36 carbs ok, fuel getting through.
I've swapped over coil feeds to eliminate coil fault.
Ignition sensor is picked up from pegs on the flywheeel.
I followed the advice in Guzziology for position of the flywheel on crankshaft (page 9-22 thanks Mark C)
I've videod the sparks with plugs out. https://youtu.be/AgOHyrlkhYA
Plug on the right is for left cyl.
When slowed down, it is clear that the left cyl is firing before the right.
Is that correct?
Symptoms sugest that the timing is wrong.
With 6 bolts fixing flywheel to crank, any miss position would throw the timing out by 60deg. So probably wouldn't run.
Any ideas anyone?

[Weg]

Woops, had the wrong listing on the video. It should work now.

Done some more research with timing disk.

The drawing shows where the trigger posts are on the flywheel.
If the flywheel is rotated on the crank, I'm not positive that B would actually trigger Left cyl.

[Weg]

Screen shots taken from video while engine was running.
Using strobe light.
Start vid is before engine was started, R on TDC.
L plug vid is running L cyl ok, being triggered by D.
R plug vid is a mystery as to what is trigering the spark.

[Throwley]

Just a thought, and I don't know the Digiplex unit at all, but are you sure the posts are actually for triggering?

Could it actually work like:

• The first double-peg is the datum point. It gives two pulses as it passes the sensor and the ign. unit bases its positional calculations on this point (the second pulse, I would assume).

• The ign. unit then looks for the counters. It knows the position of these relative to the datum and uses the elapsed time from the datum passing to calculate crankshaft rotational speed and position.

• It then uses this information to calculate a firing point for each cylinder and sends out the signal to the coil at these points.

Of course, this doesn't help with fixing your issue, especially as if it does work in the way I suggest the trigger timings will be based on a map/lookup table which cannot change!

[Weg]

Thank you Stuart, that does make logical sense.
One possible explanation is that the Digiplex unit has not come from a Callifornia but another bike that had a completely different map.
An engine that runs anticlockwise would seem to fit the bill. Hmm.

[Throwley]

Ducati bevels are the only 90deg V-twins which run anticlockwise that I can think of.

As I say, I don't know the system at all. Is it possible to flip the trigger wheel? Doing that would result in A2 being the wrong side of A, which would skew the datum.

[Weg]

Further video pictures.
Left cyl is firing 45deg before Left TDC.
Recommended at tickover is 8deg.
I would not have thought it would start at that setting.

There is an extra wire from the control box for advancing ignition. This only seem to make 2deg difference when earthed out.

This is the wiring circuit for the Digiplex.
The unitis the correct model for the Calli 1100 I have.

[Weg]

Here's a video with timing disk pointer at Left tdc when left cyl was at tdc
https://youtu.be/5fp1rLnhq2Y

[Weg]

Further pictures extracted from new video.

1. Pointer set to Left tdc. Tickover is 1100-1200
2. Coils used for strobe are as originally wired to their correct coils
3. Plug leads are swapped over to get it to run.
4. The R coil (marked on cardboard) is firing Lcyl approx 50deg before L tdc. It runs but only just, kicking back on startup.
5. To get R coil firing for R cyl, FLYWHEEL would need to be rotated clockwise (viewed from rear) 60deg on CRANKSHAFT.
6. The advance would then be about 20deg before R tdc (with leads on correct plugs)
7. Looking at L coil picture, this would then put the L coil in the correct place.

Is this logical?
I may have put the flywheel in the wrong place but feel certain it was as per Guzziology instructions.
Not like them to get it wrong though.

[EricStarmer]

Tony - I imagine you've already scoured the internet for help, but is this any help ?
https://www.guzzitech.com/forums/thread ... tion.4701/