78 R100RS 4 way flashers question

[stevenrankin]

Does anyone have a 78 R100RS with the factory four way flashers? When using the four way flashers does the turn signal indicator light flash as well as the light in the flasher switch? On my 84 R80RT it does not. I cannot remember if it did on the RS or not, it has been 17 years since the bike was last together. I am having it rebuilt now, the shop owner called and says he is having a problem with the turn signal indicator light not working yet, the turn signals work as well as the four way flashers the indicator light in the dash does not light.
Also, does anyone have a wiring diagram for the four way flasher system? The wiring diagrams I have do not show the four way flasher system. St.

 

[20774]

Snowbum has his own notes drawn on the diagram here:

http://bmwmotorcycletech.info/misclelectrical.htm

 

[stevenrankin]

Thanks

Thanks for the reply and the link to the wiring diagram. St.

 

[stevenrankin]

Thanks for the help and wiring diagram!

The link to Snowbum's website with the wiring diagram for the four way flashers solved not only this problem but solved my other posted problem with the turn signal indicator.
Not sure what wire was out of place but there was one wire plugged in the wrong spot.

The four way flashers work and yes, the turn signal indicator light does flash along with the light in the switch. St.

 

[20774]

A two-fer!! Very nice!

 

[stevenrankin]

Now about an R80RT four way flasher system

Alright gang, I got the problems solved for the 78 RS. Now it has me wondering about my 84 R80RT. The turn signals work fine, the indicator works on the dash when they are blinking. No problem with the turn signals. The questions are: One, is the turn signal indicator on the dash supposed to light up and blink when the four way flashers are in use? It does so on the 78 RS (Now it does thanks to your help). Two, does the wiring diagram from Snowbum's web page cover the four way flasher system for the RS bike and the 84 bike or is there another wiring diagram for the R80RT four way flasher system? Third, does anyone have a copy of the wiring diagram in English?
Thanks for the help. St.

 

[stevenrankin]

Four way flasher wiring harness

Upon looking at the wiring harnesses for the four way flashers to fit a 78 R100RS and a 84 R80RT, in Max BMW's microfiche, it appears they are one and the same. So the German wiring diagram I now have for the four way flasher installation on the 78R100RS is the same wiring diagram for the four way flashers on the 84R80RT.
Okay, on the 78 R100RS my problem was a wire out of place. The shop working on the bike found it after pouring over the wiring diagrams for the 78 RS and the flasher diagram. So the flasher diagram is the same for both bikes. What is the main difference in the turn signal wiring between the two bikes? I was told at the shop the 78RS has a different wiring diagram than the 84RT. I can see this to be true as the flasher units for the turn signals on the 78RS is a different part number in the microfiche with part number 01 61 31 1 358 194 for the 78RS and 02 61 31 1 244 392 for the 84RT.
So, it looks like I will have to buckle down and find out how the indicator light on the dash is energized when the four way flasher system is turned on. There is a wire out of place somewhere.
I wish I could read wiring diagrams better and that I could read German. St.

 

[lkchris]

It's a pretty cool bit of electronic trickery that requires the ignition be switched on to activate the 4-way flashers and then permit them to keep flashing once the ignition is switched off. Doesn't work that way with a single turn signal, of course. No vandal can come by and switch on anything when ignition is off and key removed.

 

[stevenrankin]

Nice to have someone send me a wiring diagram

I don't think we could have figured out the problem if I had not been directed to Snowbum's web page and his copy of the four way flasher wiring diagram.
Now, I have a feeling my R80RT four way flasher system is not wired correctly.

The gremlins jumped off of one bike on to another. St.

 

[stevenrankin]

It's a pretty cool bit of electronic trickery that requires the ignition be switched on to activate the 4-way flashers and then permit them to keep flashing once the ignition is switched off. Doesn't work that way with a single turn signal, of course. No vandal can come by and switch on anything when ignition is off and key removed.

Hey, you are correct it is kind of cool. Much easier to figure once I had the wiring diagram. Now I have to look at my R80RT and find out why the turn signal light in the instrument cluster does not light when the four ways are on. It is supposed to.

Gremlins, I need a bigger stick to beat them off the bikes. St.