Electrical Woes

[Bonehead]

Today I decided I would try to figure out some of the electrical problems with the bike. Just as a note, it was with a battery that came with it and has been sitting for a while. Max, at the beginning, it had 10V across the posts. Yes, yes fully charged battery should be used but it was just a test, not the stator papers. All voltages were taken with the negative probe on the battery (-) except for the coil readings which were were taken in the (+) (-) of the coils.

Question
I started with the coils/the killswitch and got zero volts at both (even with the solenoid jumped for good measure, to check if my killswitch/starter button was a dud). Negative probe/positive probe in the right places annndddd 0.00. I think my ignitor may be a problem? It would make sense to me but there could be something I am amiss on. I will be pulling back the tape to take a look at the rest of the harness that has to meet the coils/starter relay.

Voltage across the posts, with just the ignition key turned


Across the posts with solenoid being jumped


Voltage from the fusebox (checked all the fuses as well all checked out)


Voltage from R/R



So obviously, a new battery is in order. May get an R/R too, just for peace of mind. I need to pin this down so I can get my new spark plugs a workout

[rustybronco]

Yes, obviously it needs a new one.

You need to chage the battery and load test it before condeming the battery as bad, then you will be able to correctly judge weather or not the starter is the reason for the extreme voltage drop when jumping the starter solenoid.

[Bonehead]

Yes, obviously it needs a new one.

You need to chage the battery and load test it before condeming the battery as bad, then you will be able to correctly judge weather or not the starter is the reason for the extreme voltage drop when jumping the starter solenoid.

True. If I remember correctly I think PepBoys does it for free (load test). I will definitely be getting another one regardless, but for now this is for testing purposes and it'll (probably) work. I will just charge it and see the voltage between the posts when its done, as well as get it load tested.

[Agemax]

if the battery voltage is down to 10 volts already then shorting the starter solenoid will drag it right down, 10 volts is not enough to spin the motor and it is trying to suck all the power out of the battery.
put it on charge for a while until you get it up to around 12 volts then short the solenoid again with the charger still connected, see what happens.
i would still suspect that the battery is U/S and needs replacing

[tom203]

Yeah, sounds like battery is no good. But how far have you progressed in cleaning the electrical connections/ switches?
Avoid buying stuff till you know what you need- my hunch is the ignitor on the 650 shafties is very durable . Remember that ignitor grounds out ignition coils, so testing for voltage drop across coil terminals is deceiving - but you can unplug coils and test for 4 ohm primary resistance.

[Guest]

Yeah get the battery checked out first, if its bad, start looking at battery replacement, lots of choices out there. Before you decid to start replacing electrical components, clean/replace any and all corroded and burned connections, fuse box included.. Once that is done, do a complete charging system check to make sure there no problems there. Then do what ever other checks you been advised to do here. It is a process of discovery and elimination. Oh and a surprise or two.

[argonsagas]

If a battery is down to 10volts, and has been down for some time, it may be sulphated, and that often destroys the battery.


There are some chargers available that are able to electronically dissipate some of this, and if it is not too bad, they may be able to restore the battery.

Ask about this at the store, as it is always a good idea to have a decent charger handy, anyway.

[Bonehead]

Just a quick question before my responses. I was looking at a couple batteries, and wondering some of your input on them. This Ballistic EVO2 8 cell LiOn battery vs this gel sealed battery. I may try the gel battery simply for the forum sake and have a bit of fun testing it. EVO2 for further down the road when I relocate the electrics. Or, maybe I'm just getting too far ahead of myself

if the battery voltage is down to 10 volts already then shorting the starter solenoid will drag it right down, 10 volts is not enough to spin the motor and it is trying to suck all the power out of the battery.
put it on charge for a while until you get it up to around 12 volts then short the solenoid again with the charger still connected, see what happens.
i would still suspect that the battery is U/S and needs replacing

No wonder the starter wasn't even spinning. That was beginning to scare me tbh. But, now my fears have been (somewhat) relieved

Yeah, sounds like battery is no good. But how far have you progressed in cleaning the electrical connections/ switches?
Avoid buying stuff till you know what you need- my hunch is the ignitor on the 650 shafties is very durable . Remember that ignitor grounds out ignition coils, so testing for voltage drop across coil terminals is deceiving - but you can unplug coils and test for 4 ohm primary resistance.

Damn, I knew there was something that was nagging at me as to why the coils are getting 0V. Thanks for the reminder.

Yeah get the battery checked out first, if its bad, start looking at battery replacement, lots of choices out there. Before you decid to start replacing electrical components, clean/replace any and all corroded and burned connections, fuse box included.. Once that is done, do a complete charging system check to make sure there no problems there. Then do what ever other checks you been advised to do here. It is a process of discovery and elimination. Oh and a surprise or two.

Haha definitely a surprise or 2. I think the beginning of my wire revival will start with some brake cleaner and extensive looks at the wire diagram.

If a battery is down to 10volts, and has been down for some time, it may be sulphated, and that often destroys the battery.


There are some chargers available that are able to electronically dissipate some of this, and if it is not too bad, they may be able to restore the battery.

Ask about this at the store, as it is always a good idea to have a decent charger handy, anyway.

Hmmm never heard of sulphation but, then again I am no battery connoisseur nor do I particularly pay attention in chemistry so many things probably get past me in that region. I'll ask when I go to PepBoys. I made sure and called today that they do load testing and they did. Now, time to sneak into the garage for a battery charger

[Agemax]

i use the balistic evo2 8 cell battery on my GS, remounted under the seat. works great and is so small and light. massive cold cranking power too

[Guest]

For what it is worth, I would recommend the MotoBatt battery. In tests it outperformed all the other AGM glass matt batteries it was tested against including some with higher CCA raitings. I have used mine on four occasions to jump start cars with dead batteries. http://www.motobattbatteries.com/mot...1978-1982.html

[Bonehead]

For what it is worth, I would recommend the MotoBatt battery. In tests it outperformed all the other AGM glass matt batteries it was tested against including some with higher CCA raitings. I have used mine on four occasions to jump start cars with dead batteries. http://www.motobattbatteries.com/mot...1978-1982.html

Hmmm... I think I will go with that $30 battery from eBay I posted simply for price, and something else to test and post results for the betterment of everyone else

[Bonehead]

Added to this thread since I did not want to start another one:

I finally got a little extra from my paycheck and some time to do some research and looking. I will be getting this eBay battery for testing and to see how well it works as a cheap gel alternative.

12V 10 Ah with 180 CCA. As a comparison, the shorai LiOn battery has 210 and WOW the ballistic evo2 8 cell has 275 CCA.

After I test this battery and get the project actually moving and running well, I think I will probably move to the Evo2 8Cell.