Acceptable Voltage Drop???

[Guest]

Voltage across battery terminals with ignition on (headlight/tailight on) and not running 11.57 volts. Voltage at either coil at orange/black and orange/white feed plugs 9.07. Is that OK or considered too weak to power coils and might cause a weak spark?

Thanks,
Larry

[focus frenzy]

way to low, you are lucky to have any spark at all.

[Rocketman]

Now I'm totally baffled. I'm certain I'm checking this voltage correctly; at the coil wires feeding the coil there's a male and female white plastic connector, and coming from the Dyna S- black multi-tester lead to black wire, red to orange. Figured with cylinder 1 & 2 marginally working (if at all) low voltage might be the problem, but then BOTH coils would be shot not just one.

Please see thread I started in disgust yesterday, and let me know what you think of my dilemma. Planning on ordering new OEM coils, plug wires, boots, caps & seals early tomorrow morning.

http://www.thegsresources.com/_forum/showthread.php?t=98036

[Jethro]

Voltage across battery terminals with ignition on (headlight/tailight on) and not running 11.57 volts. Voltage at either coil at orange/black and orange/white feed plugs 9.07. Is that OK or considered too weak to power coils and might cause a weak spark?

Thanks,
Larry

Anything more than 1 volts drop is not good and indicates that something is bad and you may have more issues arise than just the voltage at the coils.

Question: what is your battery voltage with the ignition off? a properly charged lead acid battery should show 12.8 volts, 13 if it's a sealed battery. A battery at 12.5 volts is 50% discharged, at 12.2 it's 75% discharged and at 12 volts it is dead as a doornail.

[Joe Nardy]

Voltage across battery terminals with ignition on (headlight/tailight on) and not running 11.57 volts. Voltage at either coil at orange/black and orange/white feed plugs 9.07. Is that OK or considered too weak to power coils and might cause a weak spark?

Thanks,
Larry

Larry,

I had a similar symptom on my 1100E. There were a couple .5 volt drops in the circuit to the coils. Cleaning up the connectors in the headlight and applying dielectric grease cleared one up. There was also a .5 volt drop across the kill switch. I took it apart and cleaned it and greased it up as well. It is common to have a significant voltage drop across the ignition switch due to its small contacts. You can add a relay that sends power to the system directly from the battery rather than going through the ignition switch. Leon (Focus Frenzy) had a post about this a a long time ago. I searched for it but couldn't find it. I did this mod to my bike and got 1.1 additional volts through the system. It all adds up.

Good luck,
Joe

[Jethro]

This thread helped me recently. I am installing a relay to my system tomorrow:

http://www.thegsresources.com/_forum/showthread.php?t=89086&highlight=relay+ignition

[focus frenzy]

relays are your friend! a ignition relay also makes a great security addition, remove it when you park for the night and if a thief punches your ignition (most common method of theft) the bike wont start.

[Rocketman]

Thanks again for the input. Soon as I get my carbs back and installed, a set of Accel coils are going in, then we'll poke around and look for bad connections. Really never ever a problem starting, or any signs of weak battery, but we'll see.

[Arie]

...Rocket man burning out his fuses on the streets alone... { sorry couldnt resist }

Voltage drop means resistance you have bad wires or bad connections or both, and they will kill new parts just as well as they will kill old parts.

unfortunately, I know this too well so do not underestimate the importance of the following { anyone else please feel free to chime in }

take off seat, check power across each fuse - I fould bad fuses this way
take apart connectors, CLEAN them. there will be
orange - goes to ign switch
orange white is the one that goes to coils, but clean all of them
If the bike starts and runs, you can feel them get hot by testing with the back of your fingers - They are very sensitive to heat, so you don't have to actually touch to find hot wires.

after cleaning, miraculously the volatge will rise!!! Rise I tell you! Bwouuhaaa { manical laugh}

kriminy. I need to get out and ride

[Rocketman]

Glad you're having so much fun. Hope I can laugh maniacally soon. Will be in touch.

[Arie]

Trust me, when the bike is running you'll feel better. I was very much where you are now, a few weeks ago.

been there, got the t-shirt, and it burts into flames. what's worse, couldnt even get anyone to spit on me.

now that the bike is running well again, the sun has come out again.

just trying to figure out how to get it to come out when I have time to ride!