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Old R75/6 redo fuse, elec problem

mrtnfischer

Der Kaptain
:type:dohBasice 1974 r75/6 neked bike, got at a discount,
wI replaced the carbs from ebay, went to turn it over, only the headlights work NOW.

First, when I got it, and I got it home, charged battery, a;ll electrical worked, horn, lights, starter, turns sigs, etc, now notheing except the lights, I found the two headlight living fuses, but I must be missing something like a main fuse. I checked out wiring diagrams on the web but they do not even indicate fuses o0r they have them disguised. I am reading and seems they may only have two in the headlight..
Oh< I just went to the Man Cave, I think I may have a bad connection in the instrument cluster, is there a easy way to get at them... some one told me that there are plenty of place for bad connections in there. What thinkest thou????????

What am I missing here??/:blush
 
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On your bike, if it is fused, there are only two, so you found them.

Do the instrument light work? When you turn the key on (and the kill switch, obviously), does the red generator light come on?

Tell me that the kill switch isn't the problem :bolt
 
R75/6 Wire problem, 1974

Thanks everyone, here is the latest from the Man Cave.
1. Instruments do not light but originally did when I brought here home as well as cranking and all else worked.
2. High low beam works as well as parking or first position of key, 2nd position nothing, 3rd position is lights.
3. Key works as I have power to all leads out except ground (of course)
4. there is a "kill Switch" which was on the handle bars though does not look original it being a silver dished and conforms to H Bars with as Black button in center, does this present a problem the kill switch?? I will check it. or take it out.
5. I have done some probing with meter and a light, and I have printed out a Wiring diagram but they are hard to decipher not like a Jap one. Everything seems tight and good...so Here I am. The diagrams I get of the web do not seem to have the key on the side of the headlight mid left with the mounting bolt.
6. I am intrested in finding out more about the kill switch, does it kill everything but the lights?.... OK, just back from Man Cave, the Kill switch is disconnected and still everything is the same, it seems that the previous owner had disconnected the kill switch as the other end is cut and taped.
7. What is the Box on the frame like under the brake, there is a multi plug going into it?. ALso I wonder could the blinker relay be a problem, Nah just thinking

8. Remember, no instrument lights, and there were before with everything,
 
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The instrument lights are on the same fuse as the park/tail lights. Try removing the fuse and cleaning it's ends, as well as the terminals in which the fuse mounts. And check for power at the grey wire side-this is the hot side from the ignition lock.
 
R75/6 Electric Problems

:blushOK, I Have illumination lights on the instrument cluster when lights are on but only the view lights not the nuetral, high beam charge or other.

Some one told me that I may have a "Pre-Start Relay" Any Ideas 1974 /6
 
so everything worked before you rebuilt the carbs, must be the float needle thing a ma jig
seriously, I would check everything and retrace all your steps, you must have done something other than rebuild the carbs, bumped something.
ground good to tranny? neutral switch in tact ?
IM just guessing, but if it all worked before you touched it, then...........

these are not like italian machines where electrical problems can happen just by looking at them from 10 feet away( sorry old fiat mechanic, electrics were a often nightmare)
 
one more little tit bit
if your used to working on harleys, jap and brit bikes
german bikes (n cars) use the brown for ground
ground=dirt=brown
not trying to be stupid...your prob saying duhhhhh, just trying to help out
the exception on the bikes is the big ground from batt to tranny, its black :german
 
I will be watching with interest what the culprit will end up being because today I decided to devote some time to seeing if my recently acquired 1974 R90/6 is a rehabilitation candidate or a parts donor for my other two 1974 /6's (I know, I caught the bug and loose all self control when it comes to affordably priced /6's).

Anyway, I put a battery in and the only light that came on was the indicator blinker (non-blinking). Nothing else and no starter action of course. Pulling both the gas tank and the headlight assembly yielded two electrical modifications performed by a previous owner that I would like to share with all in the event that you may wish to avail yourself of these time and money saving tips.

1) Are you tired of the hassle of always having to change out popped fuses and don't have the time to run down the cause? Then simply do this - pop the headlight and simply solder in a piece of 14 guage copper wire between the opposing terminals on the two fuse posts. The cost is negligible and certainly way cheaper than buying new fuses all the time.

2) Need to replace some of the existing wiring for whatever reason and don't want to deal with or buy all those different colored wires. Not to worry. Just pick up a roll of bulk white wire at Pep Boys and go to town - it's cheap enough that you can route it any way you wish without having to follow the original harness routing. Wire is wire. Bonus tip: allow twice as much wire as needed for any given purpose (wrap the excess around the frame tube, bucket ears, or whatever) in the event that down the road you may decide to re-route the wire to a different component (like the tailight) or put in some mid-wire splices for whatever reason. It never hurts to plan ahead!

Didn't mean to hijack this thread but just wanted to share what I learned today.

Regards
 
The neutral light and charge light are powered by the same fuse-the one associated with the green-green/black wires. Did you clean and check that fuse, too?
 
IT's DA FUSE R75/6 Inst cluster, horn, starts runs

After fighting with the diagram and than deciding that it all worked before the carbs, (No it was not the carb float needle that caused the electrical problem)

I took the meter and went to the start swith, Knowing that I must have current to there in order to activate the starter solonoid. I had checked it before and swore there was power, so I checked again and NONE., Than I went back to the headlight and sharened the end of the meter probe and started going through aall of the wires to the switch, again, NADA. So I went back to the switch, every thing was live there, went back to the fuses, AND THE TOP FUSE WAS OUT OF CONTACT. Took it out, cleaned the terminal and WALA POWER. Stated first crank, so Off I went on the "WHITE TRASH" R75/6. Ran Perfect after carb adjustment.

SO
1. Never trust a FART or a FUSE
2. ALways do it twice
3. Why didn't anyone know that the top fuse controls the start, winkers and horn.....Boy was I dissapointed in all you airheads except lostboy.:groovy he had it from the start, da fuse.

It has been 30 years since I rode a Naked Bike, Wow, No Buffeting, rather quite, fun, light, and no plastic to screw with yoour brain and no worry about visability. Is this the real way riding should be? No wonder those Harley guys love. it... ANY ONE wanna buy my R1200RT with 90K, I think I am in Love with da past.
 
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SO
1. Never trust a FART or a FUSE
2. ALways do it twice
3. Why didn't anyone know that the top fuse controls the start, winkers and horn.....Boy was I dissapointed in all you airheads except lostboy.:groovy he had it from the start, da fuse.

It has been 30 years since I rode a Naked Bike, Wow, No Buffeting, rather quite, fun, light, and no plastic to screw with yoour brain and no worry about visability. Is this the real way riding should be? No wonder those Harley guys love. it... ANY ONE wanna buy my R1200RT with 90K, I think I am in Love with da past.

What we have learned here is that we want to start with the easy stuff first. As to your dissapointment, that's why we want to run an issue by as many riders as possible. Most of us on this message board are specialized to the specific model we ride. For example, I know /5's inside and out. /6's to a lesser degree and just acquired my first /7. I will now be learning the /7 specific issues going forward. I generally don't respond to inquiries about later bikes and then only on things that I know about specificly, or that are the same as earlier bikes. The members here are pretty sharp, but the best and most experienced minds are on Airheads@micapeak.com. You'd do yourself a great deal of good to find that list and subscribe to the digest form.
 
R75/6 Yes, Dissapointed but Guilty myself

True as you say, everyone has the specifics on special /5 /6 /7 and the diagrams leave much to need., I didn't want to go for a good diagram on the web as I felt I could sleuth it out my self. Back in the 60's when I taught Auto Mechanics and Printing in High school all was easy, and I defied the airhead to beat me. It is jsut the simple fuse has caused me problems over the years from my Packard, Tr 4 and 6, Goldwings etc etc. This airhead R75/6 is number 37 of my possed bikes over the years and the 2nd R bike, (First was New in the 70's a R90 with a Vetter). The Vetter ruined the bike due to its weight and I never had another desire for a Air head

It is just that to know that the upper fuse is the main FUSE is worth a lot and should not be taken lightly. Better to reinforce the IDEA, than be wondering on the side of the road, what fuse does what.

I really thank everyone for the help.:kiss
 
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