65LS wiring..

[its_only_me]

the Tacho on my 65LS has never worked so today I stripped the pod to get to this area, and although I never found a reason for a non working tacho, I did notice a pair of Green with black wires in a connector not connected to anything, I also noticed a spare terminal on the back of the ignition switch, next to these wires.
So I then looked in the Clymer manual, but the wires listed for the 65LS on the wiring diagram don't match what I am seeing on my bike, so here is a picture that I hope will make it all clearer....



so can any of you tell me what is right or wrong, and would this loose pair have anything to do with the Tacho not working?

[Rob Valdez 79 R65]

GNSW (green/black) has something to do with the turn signal/brake light circuit.  (in my '78-'80 owners manual)

And there is one unused connection on my ignition switch, as well.

I don't think these two go together.

Here is a link to a '81-'84 wiring diagram, thanks to fellow member, trolle!
http://www.tannis.dk/bmw/bmw%20r65-2%20wiring.htm

[Chris_in_BC]

Rob is right, there is normally one blank spade on the ignition switch. From memory it is live all the time independent of the key.

I also think the green/black wires might be for an optional clock.

[Rob Valdez 79 R65]

It would appear that green/black is 12v+...

[Justin B.]

I think you can move the wire that powers the hot circuit over to the unused terminal to, in effect, give yourself a headlight switch.  I think that is the way the PO wired my wife's bike so when the key is in the number one position the bike will start and run but the headlight does not come on.  Turning the switch to position two then turns on the headlight.  I think  it is kind of a neat way to work things but have been too lazy to adapt it to my R100.    Someday...  

[Rob Valdez 79 R65]

I was disappointed to find my accessory 4-ways only operate in the "headlight on" position, so I had to run lights on, engine off while I cleaned up after a discussion with the local law enforcement officer about my speed... and warned to slow down... (whew!).  At 1:30am I was happy to have the 4-ways.  

[nhmaf]

According to my edition of the Haynes manual, the wiring diagram for the 81-84 R45/R65/R65LS/R80ST
doesn't even show a tachometer !  hmph !


But, it does show that the green/black wires in the 2 pin connector are intended for connecting
to an optional voltmeter.  Must be a remnant from the other R45/R65/R80ST models that
share the same basic wiring harness as I wouldn't know where one could fit a voltmeter on
an LS with the cockpit fairing on and low bars (maybe with the US-high bars, though...).
Those wires are a straight connection to the fuse panel.

I did scan the wiring diagram in the Haynes manual, but the JPG resolution doesn't help it
much for legibility - I can email you a better quality image scan if you want one, but again, as
it doesn't show the tachometer anywhere, I am not sure what other errors or omissions it may have !
 

[Rob Valdez 79 R65]

The clock and voltmeter were factory options for the standard R65s from the beginning.  I don't know if they would have fit the LS or not, but the LS probably used the same harness as the std.

[Bob_Roller]

The electrical signal for the tachometer comes from pin 7 of the ignition control module, if you find it, note the wire color and see if you have a similar color wire at the connector for the tachometer, you may want to check for continuity on this wire from the ignition control module to the connector at the tachometer . Also, there is a printed circuit board inside the tachometer, and if I'm not mistaken, there are 3 or 4 small phillips head screws that hold the back cover on the tachometer, for acess to the indicator lights. You may want to check the solder joints, as they have been known to fail in this area. I just had a thought, and are you talking about the engine rpm indicator, or the speedometer ? I seem to remember that the terminology for these two indicators in the UK and the US may cause some confusion.