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Hello help with Ignition switch plate BMW R50s

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Marco Soffia
Posts: 7
Joined: Sat Feb 13, 2021 2:25 pm
Location: Santiago Chile

Hello help with Ignition switch plate BMW R50s

Post by Marco Soffia »

Can someone help me? I want to know where the wires come out of the ignition board. In other words, i want to know to what are they connected to:
The two brown wires,
The green wire,
The gray wire and
The yellow with a red line wire.

thanks

Marco
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IMG_0388.jpg
IMG_0387.jpg
BMW R27 1960
BMW R50S 1961
BMW R5 1937

jimcarrr100rs
Posts: 80
Joined: Sun Oct 13, 2019 2:47 pm

Re: Hello help with Ignition switch plate BMW R50s

Post by jimcarrr100rs »

The brown wires are ground. I will check my notes on the other ones tomorrow
77 & 83 R100RS, 56 R69, 74 R90/6

jimcarrr100rs
Posts: 80
Joined: Sun Oct 13, 2019 2:47 pm

Re: Hello help with Ignition switch plate BMW R50s

Post by jimcarrr100rs »

Need to know the numbers on the board the wires are going to
77 & 83 R100RS, 56 R69, 74 R90/6

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schrader7032
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Re: Hello help with Ignition switch plate BMW R50s

Post by schrader7032 »

My wiring diagrams for the /2 series do not show a yellow with red stripe wire.
Kurt in S.A.
'78 R100/7 '69 R69S '52 R25/2
Fast. Neat. Average. Friendly. Good. Good.

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jwonder
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Re: Hello help with Ignition switch plate BMW R50s

Post by jwonder »

Marco, the most important thing is the numbers on the board. They correspond to the numbers on the wiring diagram and most people on the forum can tell you what number goes to what item almost from memory.

Since you have an repop/aftermarket board the factory wire colors will most likely not match the BMW diagram. Write the wire colors and what number lug/solder point they go to and save it in the R50S folder.

I always use paint to fill in the numbers so I can see them when it is mounted upside down.

By the way I am almost done with my full restoration of an R50S and if you need anything let me know. You can email me at webmaster@vintagebmw.org
James Wonder
Vice President, Vintage BMW Motorcycle Owners
2022 BMW Friend Of the Marque
Long Island, New York

Marco Soffia
Posts: 7
Joined: Sat Feb 13, 2021 2:25 pm
Location: Santiago Chile

Re: Hello help with Ignition switch plate BMW R50s

Post by Marco Soffia »

Thank you Jwonder for you help

31 Brown
30/51 Grey
15/54 Green
56 Yellow/Red

Regards,

Marco A.
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grey 30/51
grey 30/51
green 15/54
green 15/54
yellow 54
yellow 54
Brown 31
Brown 31
BMW R27 1960
BMW R50S 1961
BMW R5 1937

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schrader7032
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Re: Hello help with Ignition switch plate BMW R50s

Post by schrader7032 »

30/51 (it's just 51 in my diagram) should be a red wire going to terminal 30/51 on the generator

31 should have multiple brown wires going to 31 on the generator, a junction connector to the rear lights, and to terminal 31 at the headlights

15/54 should have multiple wires going to 15 on indicator flasher, to a connection for the neutral/gen light in the headlight shell, and to a terminal on the horn

56 should have a couple of wires going to 56 on the highbeam/horn switch and to the speedometer indicator light

My DC circuit skills are so-so, but that is what I see in my book.
Kurt in S.A.
'78 R100/7 '69 R69S '52 R25/2
Fast. Neat. Average. Friendly. Good. Good.

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wa1nca
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Re: Hello help with Ignition switch plate BMW R50s

Post by wa1nca »

The bosch switch board was used in several other bikes like jawa only colors were different

green is same as 15/54
terminal 15/54 provides power to horn/brake light switch/flasher unit
green wire to center terminal of red/green indicator bulbs

yellow/red # 56 terminal to headlight switch power for high/low headlight beam

grey wire #58 tail light and small running light in headlight and speedo bulb (same as screw terminal next to it)

brown #31 ground large brown to #31 ground on generator/ground in headlight shell
one brown not used
Tommy Byrnes
54 R51/3, 55 R50/Velorex 560 sidecar, 64 R27, 68 R69US, 75 R75/6
Ashfield, Ma
USA

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