Emergency Power

[Mekanix]

Since its common now to remove the direct connection the RR usually has to the wiring system and wire it directly to the battery, any failure of the main fuse means you loose all power.

What happens when you blow the main fuse at night? Well its pretty scary having no power and no lights at speed.


I was thinking of a bit of extra wiring that would kick in once the main fuse blow's that gives you high or low beam and tail lights or even a 4 way flasher light system.

I'm just now starting to think up the wiring but its not that hard to figure out all the details.

I guess the reason for this post is to see what you guys would like to have as a backup system.


Something like a relay in paralell with the main fuse so that when it blows, it would cause the relay to make. From that you could have it route power to the head and tail light through some fuses.

A few diodes inline with the lights wiring would stop the rerouted power from back-feeding to the rest of the electrical system and only power the lights.


Thoughts ?

[Riding Again]

I think it would be a good idea to fault out with a default of low beam, tail light and rear flashing.

[Steve]

Since the function of the MAIN fuse is now re-purposed, it makes sense to upgrade its capacity, too. In it's original configuration, current goes through the fuse from the battery to the bike when you first turn the key on, before you get the engine running. After the engine starts, the charging system will power the bike and any excess is sent back through the MAIN fuse (in the other direction) to charge the battery. Used in this fashion, the stock 15-amp rating is just fine.

However, when you move the R/R connection directly to the battery, ALL the electrical power to the bike will go through the MAIN fuse ALL the time. Considering the total draw of two coils, a headlight, a tail light, a brake light and possibly a pair of turn signals, your potential draw could easily exceed 20 amps for a short time.

Depending on how much work you are willing to do, you can re-wire the fusebox so the MAIN fuse only provides power to the ignition switch, which will turn on a relay that connects battery power to the other fuses in the box. I have done that on the two bikes in my stable that also got Eastern Beaver fuse boxes.

Another possibility is to get a self-resetting circuit breaker and put it in place of the MAIN fuse. Yeah, you will still lose power in the middle of a turn on the darkest of nights, but you will also get it back at least momentarily, if the cause of the short has been removed.

.

[Riding Again]

I've wired the R/R directly to the battery using a 30 amp fuse and really don't expect it to blow. The installed EB fuse box is powered through the relay method and has a 15 amp fuse (main) for the relay side. All other circuits are stock amps.

I still like the idea and will think it through, but I see your point also Steve, it really shouldn't happen with the correct fuse installation. I'm certain it wouldn't happen with my set-up.

[tom203]

Mekanix said...

"Well its pretty scary having no power and no lights at speed."

Yes, happenned to me once long ago when I was "upgrading" my lighting.
If you wire direct to battery positive, use a 20 amp fuse to have a safety factor. An unlikely short will blow the 20 amp fuse as quick as a 15 .

[old_skool]

Thought I'd toss this out for some opinions, from the main to the 5 pin relay will provide power to the relay as long as the main isn't blown, preventing the circuit to complete as only 87 will have power, not until the main blows will 87a have power and complete the circuit, then your head light (low beam) and tail light will have instant power, an auto turn signal relay will flash both signals, the diodes are necessary to prevent back feed of the flashers into the opposite side during normal operation. A fuse to the circuit is added in case one of the items being powered is the cause of the main blowing and is shorted to ground, we don't need more wires melting, and protects your battery, also, a toggle switch is added so the circuit so it can be disconnected, after you've reached a safe haven or during daylight hours to prevent battery drainage. Thoughts?? Fairly cheap to make.
An additional note, you may also have dash/gauge/running lights (if installed) likely as the brown tail light feed is tied in with the gray wire at the left hand signal switch.
Might need to use a 30amp fuse instead of the 20, haven't checked into it yet.

Final revision


sorry not the neatest, just whipped up real fast for critique

[Mekanix]

I like it. I was thinking of wiring the relay in parallel with the fuse so that when it blew there would be positive from the battery and ground from what ever the short is or even just a light bulb or ignitor or coils... would be enough ground to make the relay click.

Also this way if you turn the ignition off the lights would go off. (unless there is a short in the main power feed from the main fuse to the ignition switch)

Its like using the electrical system as a switched ground. but an extra switch to turn it off in case would be alright.

All the diodes are there to prevent backfeeding.




I must have posted and edited that thing like 5 times

I think this one is functional now, although complicated.

[old_skool]

Only one other thing missing is a 10A diode inline with the headlight before the the new wire is added so the new wiring doesn't backfeed.

I'll edit the drawing to show what I mean.

Already done. There are many ways to do what I did, buy I didn't want to over complicate it, I wanted anyone to be able to do this.

One day, maybe I'll make a super harness that you can plug in camping accessories with a power inverter...not really, (maybe just a bug zapper) but with the right wiring and power source, there are a lot of things that can be improved on if your imagination will allow.

[old_skool]

If I wanted to complicate it a little, I would have given you a schematic with a small circuit board containing several large capacitors to automatically trigger all 4 signals into an emergency flasher with the loss of power, just long enough to get to a safe area to stop, maybe even a second isolated system to provide power to the ignition and coils to allow emergency power to run the bike momentary in case of an all power shut down in a dangerous situation involving traffic. A lot of times people have devoted areas of interest into electrical or electronic, I was fortunate enough to have done both. Mrs. old_skool is pretty sharp in the electronic department as well.

[Mekanix]

lol and your much faster at paint than I am too


I see the edit's now. nice


Having the headlight on was a minimum. In that case the circuit is pretty simple.

1 relay 1 long wire to the headlight and 1 diode. All the work can be done right beside the main fuse panel or hidden anywhere.

There would only be 4 connections to do and anyone could do it.

1 at the headlight with the diode and wire, two for before and after the main fuse and 1 for a fuse inline with the relay. It only takes 6 amps to run the headlight max IIRC So a 10A would work fine.


Adding the tail light is also easy to do and can be all done in the headlight bucket with 1 more wire and 1 more diode.

Its when the turning signals come it that more diodes and extra flasher make it complicated.


What do you think would be the easiest thing for just anyone to do old skool?

[old_skool]

I only see 86 grounding if your main shorts to ground otherwise it would just be an open, and an intermittent short would still possibly leave you high and dry, which is why I used a positive instead of a negative to complete the circuit, doesn't rely on the actual short to provide the circuit, just acts as a trigger.

[Mekanix]

I only see 86 grounding if your main shorts to ground otherwise it would just be an open, and an intermittent short would still possibly leave you high and dry, which is why I used a positive instead of a negative to complete the circuit, doesn't rely on the actual short to provide the circuit, just acts as a trigger.

I see what you mean. But there are lots of potential grounds that would be enough to trigger a relay.

I was relying anything in the circuit that could possibly lead to ground like ignition or lights, If anything, A few lights in the instruments would be enough to lead to ground and make the relay. And the ignition switch would still be able to turn the lights off by removing the ground.

[old_skool]

What do you think would be the easiest thing for just anyone to do old skool?

I see your way working, I'm not convinced it's as reliable, as far as ease for the everyday mechanic, would be to make most of the entire circuit on a small board to be hidden somewhere behind the side panels, possibly the passenger side, seems to have more room, then wiring remains with the remaining 4 diodes needed in the existing circuits. Easiest...get a AAA card
I'm thinking no matter what way you come up with, it's not foolproof. Concerned a little with yours, as your circuit may very well be interrupted by the initial source of the short, relying on the main to provide the ground, my way only requires it to blow it's fuse, then it's out of the circuit, see how that might be safer? Also revised mine with the rest of the diodes.



any other electrical guru's with opinions??