LM II: Ignition system and Electrics!

Struggling to identify this ignition system on a LM II.
I need to set timing and struggling to get initial set up right (have strobe and can see marks on flywheel)

Optical unit in distributor with lead going to left box in second image.
Output connects up with the second box and then to HT coil.
Second box has one RED LED, a number (P00130) but no other markings on any of the kit.
I can get the bike running and move the distributor to get marks aligned but on one cylinder.

I know I can move one of the sensors on the distributor plate but it is not making much sense.
It would really help if I knew what the system is!

Looks like might be a ‘Lumenition’ … infra-red LED’s and photodiodes and a revolving shutter … (?)

Could this be a wasted spark system? And if so will it affect the set up?
Sorry I can’t identify the unit.
Good luck

Hi, looks like it could be a pirrana electronic ignition or newtronic ignition as its known now, if it is you have to time the left cylinder first by rotating the whole distributor body, once you have the left cylinder timing spot on then time the right cylinder by adjusting the bottom pickup on the adjustable plate in the distributor housing. (The total opposite way of timing a standard guzzi with points). all the best, Chris. PS if you do a search on timing in this forum i had a post with basicly the same issue and someone attached a link for the instructions for this ignition system.

Thanks for the input - I am thinking it is a piranha ignition system as the paperwork includes a bespoke wiring diagram (well scribble in bliue biro) for it. The extra unit has slightly thrown me.
Thing is I have had to rebuild distributor as springs etc were red with rust and finding the initial set up for the distributor is not in the newtronics link. It looks like I am going to work it out the long way. I assume the rotor cut on the IR beam acts as “points opening” and the arc of the rotor is in effect the “dwell”. If I have to set the distributor for the left pot, I will need to find out which sensor is for the left, and work from there. Once vaguely in the right position I can fine tune using the strobe and the flywheel marks.

I think it looks like a Piranha system too.
Unfortunately Greg Bender only seems to have the second page of the instructions, but it does tell you how to set the ignition timing. I have a copy of the instructions somewhere and will try and look it out.

It looks Pyranna and if so if it sparks out the cylinders but won’t fire up change the 2 feeds to the coils as it was still wrong in the diagram last time I looks.
OS Electrical advertises in Gambo if you need professional help.

IIRC the Piranaha system has 2 little mounting plates in the distributor. If you set up one cylinder OK but can’t get the 2nd one right its because that one’s mounting plate is the wrong way round or upside down. DAMHIKT !!

Yes, everything is pointing to the Piranha system. The first page would be really helpful

  • I am rebuilding distributor with new advance springs and that part of the instruction detaiing setting for refitting of distributor is what I really need.

Think I’ve killed it now!
LED no longer flashing.

The nice people at Newtronics sent me these :smiley:

Hope they are of use

If you would like a pdf copy send me your email address via PM (don’t post it on here) :smiley:
A good tip with the timing marks if you want to use a strobe is to paint Tipex either side of the mark on the flywheel

What is LED for?

LED on larger unit shows ignition pulses
Just does not fire at all - spark at plug inconsistent and weak.
Can get good spark using points but they and condensers very worn/old.
All this due to hard starts and occasional misfire…
Might get new points and condensetrs to get it running then save money for new Silent Hektik system.

39 degrees advance seems a tad high for a big block as suggested on the Newtronics info, thought it was 34 degrees :confused:

got it kind of running with the old points and condenser
So new ones ordered as temp measure (how long is that piece of string!)
Think the Silent Hektik will be a long term fix.

Got a Saches Electronics on my G5 special, points on my T3 both seem to work well.

Well spent some evening time completely cleaning distributor.
Fitted new LM advance springs, points and condensers.
Set points up (first time I have dnne that for 25 years)
Fitted amf timed on both left and right (I did the contact plate mod while distributor in pieces)
Dug out couple of old car HT coils and it ticks over (for the very first time since I had it), and once warm runs up to good rpm with no issues…
Back in pieces now waiting on arrival of new HT coils and some more tidying up.
The box of bits removed is getting fuller!

What’s the contact plate mod?

Contact plate mod is a simple fiilng of left pot moveable plate so you have a wider range of adjustment
Can get both points right and full advance with no changing of point gap on left
From here: http://www.thisoldtractor.com/moto_guzzi_tonti_distributor_dual_points_plate_modification_so_you_can_time_both_cylinders_properly.html