I need some help with an electrical problem on my 79 flh

the other day I pulled it out to ride, hit the started button and nothing happened. No lights, no clicking, nothing

general bike info
the bike has a main breaker in between the battery and the ignition switch, then 3 breakers in the headlight (ignition,accesiries,lights)
there is no run switch just a tank mounted ignition switch and starter button, the starter is wired direct. If you walk up and hit the starter button it will spin the starter but will not fire unless you turn the ignition on

ok here is what I tested
battery is good
with bike off I get 12v to main breaker and to (+) on ignition switch
when I turn the switch to run I get 12v coming out of the switch and at the ignition brraker in headlight
when I turn the switch to run with lights I get 4 volts coming out of switch

I have a electric ignition switch and thought it might be bad.
I have an old manual brass bar type switch that I thought I would try, so the next day I go to swap it and the bike fires right up with the current electric switch, fires up multible times, lights seem to work fine, everything good. Then all of a sudden nothing just like the first time.

I change the switch to the manual one and same thing
With the switch off I use a jumper wire from the (+) to the lights and all the lights come on
I use a jumper wire to the ignition wires and nothing, also during all this I should be able to spin my starter but it will not, no click , no smoke, just nothing

If I wire up all the wires that should be hot coming out of the switch I get the same results
After a couple hrs of not touching the bike If I walk out and turn the ignition to run/lights all the lights come on then when I hit the starter button nothing happens and lights now stay very very dim and I get low voltage tests in areas that tested 12v before hitting button


my brain shuts of with electrical trouble so I could pleae use some advise and some things to check

 

How did you test the battery?

The starter button is wired direct...to what?

 

I tested the battery with a simple volt check, I did not do any sort of load check, I think they will do that for free at the local auto zone. The battery is also less than a year old

the started button is wired direct to the solenoid, it is a basic round push button. If I try to jump the solenoid nothing happens.

thanks

 

Your`e not giving up much information here..can`t help unless it is known exactly how the circuit is wired since it is not original.

The starter button is wired direct to the solenoid, well, what else is it wired to? It needs power from somewhere....

Good luck.

 

ok sorry about that, it is not intentional

I believe it goes like this. There are 2 wires on the starter button, one goes to (+) on solenoid and the other goes to the small stud on solenoid (where a relay would go) the solenoid goes direct to the battery and starter. I might need to double check this when I get home.

From long stud on selonoid I have 12 v
from short stud on selonoid I have no power until I push the starter button, then I have 11

 

If you have already tried to use jumper wires and/or a brass starter button, then maybe the starter motor itself is going bad. I suspect a short in the starter motor which could be intermittent and allow it to work part of the time. The fact that power goes dead when you attempt to energize the starter motor seems to point to an extremely large voltage drop I would associate with an abnormal amount of current draw. Since the lights, etc. otherwise work normally, I would conclude that it most probably is the starter motor. But, we need more info. to be sure. Does the power wire to the starter motor get warm or hot? Was there supposed to be a relay in the starter motor circuit originally? You also need to do a load test on the battery with it OUT of the motorcycle or all of the wires attached to it to be removed during the test.

 

Sounds like multiple issues...

When you say "hit the started button and nothing happened. No lights, no clicking, nothing", it sounds like a ground issue. Tighten all cables both ends.

Assuming you have a multimeter. you should have 12.4 - 12.8v at the battery. When you have the lights on and try to start, you should go no lower that 9v, When the bike is running, you should go up to 14, higher when you increase rpm. So first thing first, recheck your battery to make sure it is good including load...and your charging system is functioning properly. Battery health has nothing to do with age of battery....I've seen multiple times new bikes with bad batteries,

 

it is not un common for any of the brakers to go bad and do this - jump across the braker with a jumper wire see what it does

if its the same re charge the battery - and use a volt meter across the battery when turning the ignition on to lights - read the voltage, if you start at 13 plus volts on the meter - you should still be up close to that turning the lights on -- a 11 volt reading at the battery right away -- its shorted the battery don't care if its a week old

 

last night I took the battery out to get tested at the auto parts store and it tested good

what I found was a bare spot where the main ground cable off the battery had been rubbing on the oil tank. I took the cable off and on the under side there was a nother large crack in the insulation. The cable was sort of cramed in there. some of the copper was frayed at the frame connection too.

also found a bare spot on the wire that goes from the voltage regulater to the battery

I replaced both these and everything seems to be working fine for now

 

A ground wire can be Naked in Fact... no harm in grounding the Ground Wire...
Grounding the plus side of the battery however... breaker suffers... if yer wired with all [including the Voltage regulator] fed thru the main breaker...