LAVERDA 1000 SFC Superleggera Part one

Tom, the clip ons are made by Mirco Messner Moto (messnermoto.com), as described on page one of this tread. Only available anodized black.
They are made in different sizes, but not 41,7 mm for the Marzocchi M1R 🙃. They supplied me with some aluminium pieces 0,1mm trick.
That was not good enough to fasten them properly, so I added som very thin blades from a feeler gauge.
 
RGSFC said:
And yesterday came came the big moment, where I could finally attemt to start it. The small battery gave an impressively fast starter speed,
and then nothing….. checking spark- no spark.
This is as far as I have come with the bike. I am aware that it will be based on very little information, but any suggestions are most welcome.
Click to expand...

A quick way to check the ignition wiring & components -
1. Put the microswitch on the DMC box to position 0.
2. Remove and put the spark plugs in the plug caps.
3. Ground the plugs on the cambox cover.
4. Switch on the ignition. Manually turn the ignition rotor clockwise and you should have a continuous spark when the cutouts in the rotor pass the photocell.

Do not touch the sparkplugs when doing this test!

Full installation and test details are here -
Library link
 
The first time I saw John's EI test function, the grounded plugs sparked constantly starting at 2,000rpm and then jumped up 1,000rpm at a time till redline. It looked and sounded like a MIG welder, so cool. Touching it would be a very BAD idea
 
Vince said:
The first time I saw John's EI test function, the grounded plugs sparked constantly starting at 2,000rpm and then jumped up 1,000rpm at a time till redline. It looked and sounded like a MIG welder, so cool. Touching it would be a very BAD idea
Click to expand...
Depends... when you have atrial fibrillation or a heart attack, it might even solve a problem (or cause another, bigger one...?) 🤪 😇
 
either dead DMC or bad connection in the wiring. Just because I fell in that trapp, too: The run/off switch on the right handle bar is on, right?
 
Then check if you have current on the red wire (16?) on the DMC (3 I suppose?) with a multi-meter. If so, check if the ground has connection by measuring between the red (I think) wire that delivers the power from the key-lock to the DMC and the (black I assume?!?) connects to the battery minus pole (hope you have it directly hooked up to the battery, not to the frame?!?).

If that all works and no spark on the spark plugs, check the current on the coils and the minus connection from the coils to the DMC.

We also had it once that the little pin-connector from the multi-plug at the DMC slipped out of the plastic, so that - even though the multiplug was correctly installed - the DMC did not get any current.
 
DMC 3 and battery minus: check:) Electricity is not my favorite field, but I will measure and check the Earth connections
 
make sure you measure it at the dmc itself so you are sure it has ground and plus, please. then onto the coils

The coils must have plus permanently coming from the key lock, as the DMC times the spark by opening/closing the ground wire coming from the coil to the DMC to my understanding. Also check you did wire them the right way (plus from the ignition lock going to the three plus connections of the coils, each ground connection to one of the 3 ground connections of the DM).


if that all works, the next thing to check is if you mixed up some wires at the DMC. If that all is OK, I would assume you need to talk to Uwe Witt, as the box might be shot.
 
So far I haven’t found any faults at all. Even the multiplug from the DMC looks perfect. I will request the help of a friend that is very competent to come by, and measure it all. It’s still a 40 year old bike, and many years ago somebody modyfied some parts of the electric curciut- and not very
nicely. Then I come along and change a lot of things as well. I bought renovated switches for the handlebar, ,and particular in the the left one the wire colors and position in the 9 point plugs are totally different, so better start over and check the complete system.
 
So - what were the results, please - you have measured current on the plus wire at the DMC and at the wire on the coils, ground connection is also measured OK, all connectors in the big plug of the DMC3 are tight and reach down completely (if you look from the under side of the big plug)?
 
Yes Lothar, I checked it all (with my limited electric skills) There is power to the DMC and the coils, and the big plug looks perfect
when looking from underneath- the 8 pins are precisely the same length, and all are parallel.
The only thing that strikes me is: The battery has just over 13 V after the start attempts, but on the red DMC wire and the coils, I
only measure just over 12 V. I don’t wheather this is normal? In any case, my skilled friend will check the entire wiring loop this
coming friday
 
some resistance on the way might acure and can cause the drop in voltage. Main point is to see what voltage goes into the DMC when you hit the start button and the engine turns. DMC doesn't like voltages below something like 9,8 or 9,5 Volt
 
Lothar, I think that I (more by luck, than good judgement) located the problem. I was a little concerned that I might have damaged one
of the 4 small wires to the photocell during installation- not a lot of room there, and the last 5 cm was not covered by a protective black
tube. Even though I had covered that area with gaffa tape, I thought that I better check it. When I removed the tape, there was no damage.


IMG_1303.jpeg
 
Sorry for the broken message. I then followed the cable backwards under the engine and into the battery box, where a tripple plug
was located. I took it apart and it didn’t feel right. Two of the tree pins were loose and obviously not in a position to make contact with
the other part of the plug.

IMG_8069.jpeg
The Irony of it is: I spend some time searching for good quality watertight plugs, and ended up with a german company, Craft Meyer.
I bought a large selection of them from 1-6 pins. The last weeks I have tried to use them, af found that that they a quite difficult to assemble
correct. Half the times they come apart, even after studying how to on Youtube. Witt is using the same brand, and apparently they are not
able to do it either;)
 
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