Certainly was not badmouthing BMW electrics, I mean, like James pointed out, many of these are 40+ years and many, many miles old. Simply responding to Wobbly's comment, "BMW used this relay to take a very shoddy short-cut on Airheads." I still find it incredible that BMW still sells most parts for these bikes and that they are still serviceable after all these years and miles.

Thank you VERY much for sharing. From their appearance (very oxidized silver) both my regulator and relay appear to be OEM, but untouched by brake fluid, thankfully !

The metallic relay cover means that most likely IS the original relay. That metal relay cover has a tiny hole to allow water to escape, but it also allows brake fluid to enter. I urge you to pop off that cover and inspect the interior before electing to continue using that relay. You might just change your mind.

Certainly was not badmouthing BMW electrics, I mean, like James pointed out, many of these are 40+ years and many, many miles old. Simply responding to Wobbly's comment, "BMW used this relay to take a very shoddy short-cut on Airheads."

...A statement made becasue which rider, having been stranded on the side of the road with electrical issues, would think to remove the fuel tank and look at the starter relay as the source of the issue ? 'Yes' the tank might eventually come off, but only after an hour inspecting the headlamp wiring, ignition switch, and other areas. And the BMW schematic leads one to believe the primary connection between the battery and ignition switch is completed with a single wire, running straight through. The reality is that we have 2 separate wires, joined together by relay terminals.

All the best.

Just to close the loop, my New Year's Day project was to disassemble and inspect the starter relay and voltage regulator, both of which appeared to be original. Sure enough, the screws holding the regulator onto the frame had not apparently been removed for 40 years. Upon examination, while there was some corrosion on the hard metal internal parts, all the electrical components were pristine: copper windings still shiny, contact points clean, etc. Sprayed some contact cleaner on all connections nonetheless, a light coat of De Ox It and silicone sealant for the covers. Hopefully, I didn't jinx anything!

Phil, my take on would be that starter relay on the left side of the frame back bone is much more likely to give you "funny" stuff in your electrics. The voltage regulator can only do 2 things. 1), being that if it fails to allow charging, the battery will go dead. 2), if it fails to regulate it will cook a battery on longer trips and kill headlights. It took me over a year to figure that one out. Then, only after I got to thinking about British (Lucas) electrics when I applied my long forgotten understanding to the Bosch system. My batteries would go dry on the cell nearest the poles, and I was popping headlight elements. Those are the most likely results of a failed regulator.

The more important thing here is that we are sharing insights in to our experiences. Wobbly, and Scott M., and a host of others are educating a new set of owners.

As a new Airhead owner, I REALLY do appreciate the support and answers from fellow members of ABC, including you. Yes, the regulator looks like an on/off only, so I plan to buy a spare starter relay and carry it in my took kit. Thanks to all for the help. Gremlins not identified but banished . . . for now.

Just to close the loop, my New Year's Day project was to disassemble and inspect the starter relay and voltage regulator, both of which appeared to be original. Sure enough, the screws holding the regulator onto the frame had not apparently been removed for 40 years. Upon examination, while there was some corrosion on the hard metal internal parts, all the electrical components were pristine: copper windings still shiny, contact points clean, etc. Sprayed some contact cleaner on all connections nonetheless, a light coat of De Ox It and silicone sealant for the covers. Hopefully, I didn't jinx anything!

• If a person wanted to update their electrical system, there are now fully electronic voltage regulators that are an exact physical and electrical match for the Bosch OEM for under $20. The advantage being that there are no contacts to get dirty, or settings to go awry. All these functions are pre-set by electronics, that are then fully enclosed in epoxy to make sure they are impervious to almost everything. Look on Ebay for them... such as eBay item number: 272655228783

• If you were to buy a replacement starter relay, then I would seriously consider installing the new one, and having the OEM part as the tool tray backup. This becasue the new one, having bright shiny terminals, is going to make slightly better connections between the 2 portions of the Positive supply trunk for the main harness. That could result in brighter lights and other advantages.

Hope this helps.

such as eBay item number: 272655228783

Absolutely amazing. How do you learn/remember all these details?

 

Absolutely amazing! How do you learn/remember all these details?

you may not like this answer

butt

GO thru ALL wire connections over the winter and TIGHTEN every spade connector, SCRAPE every male female spade connection ..... and make sure every one is Tight and Clean ! !

that should hold you for a good 4-5yrs of riding.

ps ...... you will LEARN a lot about your bike 😛

you may not like this answer

butt

GO thru ALL wire connections over the winter and TIGHTEN every spade connector,

SCRAPE every male / female spade connection ..... and make sure every one is Tight

that should hold you for a good 4-5yrs of riding.

Harry and St. I hear you and will undertake that project if problem reoccurs. I'm in the middle of ideal riding season here ;-))