[Solved] 1980 R100RS: Did my ignition switch fail?
![Eric Druse](https://www.airheads.org/wp-content/uploads/2023/01/abc-logo-190x190-1.png)
thanks Richard. The cleaning is underway!
I guess I didn’t bother fixing the voltmeter because I was told they rarely provide accurate readings and it was more of an accessory. Is there a good replacement you would recommend? Or is it possible to rebuild?
thanks
![Steven Rankin Steven Rankin](http://www.airheadsbeemer.club/wp-content/uploads/wpforo/avatars/14724_3939.jpg)
LOL, a tip off is if the buzzing noise is coming from under the gas tank, it is most likely the relay coil if failing internally.
Then again since the power for the headlight system comes the relay, a bad starter relay could make the headlight relay buzz as well because the coil in it is confused by the screwy flow of electric from the starter relay. I see more starter relays fail even when master cylinders are not leaking on them then I see headlight relays fail. Who knows perhaps BMW could have used a more reliable relay for such an important part.
My first BMW mechanic told me the two most important gauges to have on a bike are the volt meter and a clock.
That aside, the charging red light will tell you just about as much while riding about charging as a volt meter. If the light is on while you are riding above 1500 or 2000 rpm, you have a no charge. If you turn the key on and no light comes on, you have a bad bulb or other issue, still not good.
Not all BMW airheads had voltmeters installed and lots of guys myself included rode a lot of miles without. I only have one now because the bike came with it in the RS and RT fairings, and even that was if I recall on my R80RT and option.
Oh by the way, the volt meter being dead is a non issue as it as unlike the old amperage meters, it is not wired in series in the circuit,
A failure with an amperage meter could cause no charge. One more thing to go wrong and for the most part why voltmeters took over the job of reporting charging system health. or maybe it was due to the change from generators to alternators, I don't know for sure. good luck, St.
Beware! I do not suffer fools gladly! St.
![Richard W Richard W](http://www.airheads.org/wp-content/uploads/wpforo/avatars/wobbly_12394.jpg)
Used ones are easy to find on eBay.
Due to the harness wiring they all tend to read 1 volt higher.
Owning an old Airhead is easy.
Keeping an old Airhead running great is the true test.
![Eric Druse](https://www.airheads.org/wp-content/uploads/2023/01/abc-logo-190x190-1.png)
New starter relay arrived today. Gave everything a good cleaning and plugged it in. No ticking sounds no flashing! First key turn there was a little smoke that came off the relay and freaked me out. Immediate turned off and rechecked all my connections were correct. Also had a little spark on one of my wires to the coil. Yikes. Found it a tad loose. Went through it all again and then turned the key. Nothing abnormal this time. I am guessing was just a bit of factory protective oil on the relay terminals burning off. Flicked the ignition switch, also fine, nothing abnormal. Tried the starter button and she fired right up. Spending the rest of the afternoon continuing the clean and applying no ox id.
Thanks all for the help as always!
![David Elkow](https://www.airheads.org/wp-content/uploads/ultimatemember/592/profile_photo-190x190.jpeg?1725754588)
Very cool. Congratulations.
![Steven Rankin Steven Rankin](http://www.airheadsbeemer.club/wp-content/uploads/wpforo/avatars/14724_3939.jpg)
Very good news!
As Richard says, there are V meters on the web used and unlike the original clocks, they are I find pretty reasonable in price.
Also, there are other companies making units that will fit the bike, right now I can't think of one other than VDO. LOL, at least I see them installed on airheads, I can't say for sure they fit direct with not hassle.
Anyway, good news, go ride and enjoy. St.
Beware! I do not suffer fools gladly! St.
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