contact plate connection

[Montunatogiorgio]

Hi everyone, I'm new to the forum and this is my first time posting.
I'm redoing the electrical system on my 1972 Laverda 750 SF.
I would like to know from those with more experience, where the contacts on the plate inside the Bosch headlight are connected.
the number 31 is the mass
15/54 is the positive
30/51...
Ho....
56....
61....
thanks to whoever will give me a hand

 

[Jo]

Ciao,
there is a library in this forum - also one for your Laverda. Try this for example:
Laverda 750 Operation Maintenance and Parts Manual

 

[DavidH]

I would suggest that you use the wiring diagram as a basis for your check.

Our 72 SF wire colours onto the headlight mounted switch in no way match the wiring diagram with regard to colours.
Use of a multi meter, patience and a couple of pleasant hours investigation tracing wires will bring you the answer.
A nice red wine can also help.
From my experience, look for joints buried in the wiring harness around the steering head if the colour varies at the ends.

Good luck.

 

[arancia]

Hi everyone, I'm new to the forum and this is my first time posting.
I'm redoing the electrical system on my 1972 Laverda 750 SF.
I would like to know from those with more experience, where the contacts on the plate inside the Bosch headlight are connected.
the number 31 is the mass GROUND = Earth in English
15/54 is the positive
30/51...
Ho....
56....
61....
thanks to whoever will give me a hand

I sympathize with the challenge of trying to fix the switch and get the wiring sorted out in the headlights using the Bosch plate switch - I have a couple on the bench trying to repair and mix and match between the parts in the Laverdas and spares obtained from BMW sources as the same switch assembly is also used on /5 model BMWs.

There are sources of information in BMW forums, for example, BMW forum ignition switch page
which provides information about the switch wiring and which contacts are connected at the positions of the key switch on the /5 models, copied here in case that source disappears, there's no copyright statement that I can see on that page, colours per BMW spec and your bike may vary.

(I'd set this section into fixed spacing font Courier New but that seems lost when read back from the forum, in "edit" mode it all lines up but then when saved and read back looses all the spacing - perhaps somebody more expert in how this forum works can fix that?)

light ignition
HO 56 58 30/51 15 31 switch switch
+-------+-------+-------+-------+----------------+
| | | | | ########### | OFF OFF
+-------+-------+-------+-------+----------------+
| | | ########## | ########### | PARK OFF
+-------+-------+-------+-------+----------------+
| | ################## | ########### | ON OFF
+-------+-------+-------+-------+-------+--------+
| | | | ########## | | OFF ON
+-------+-------+-------+-------+-------+--------+
| | | ################## | | PARK ON
+-------+-------+-------+-------+-------+--------+
| | ########################## | | ON ON
+-------+-------+-------+-------+-------+--------+

Horn Headlight Park Positive Ignition Earth

black yellow/ grey red green brown
white

*************************************************************************
*************************************************************************


/5 Ignition Switch Terminal Layout:
----------------------------------

FRONT
+-----------------------------+
| |
| * o o |
| 30/51 31 2 | viewed from below
| | (as mounted)
| |
| _ _ |
|/ \ * / \|
LEFT | 58 | RIGHT
|\_/ \_/|
| |
| |
| o | * - terminal
| 56 | o - insulated terminal
| * |
| * HO 15 | terminal 2 not used
+-----------------------------+
REAR

Admin: Rather than hack about with style templates, I've added the information as a pdf which has preserved the original spacing