(06-03-2018, 12:51 AM)edd_of_the_hill_imp Wrote: [ -> ] (06-03-2018, 12:35 AM)SportsterDoc_imp Wrote: [ -> ]Define "battery fine":
1. Battery voltage key off?
2. Battery voltage key on?
3. Battery voltage while pressing starter button?
http://xlforum.net/vbportal/forums/showt...651&page=3
1. 12v
2. not sure
3. not sure
(06-03-2018, 12:41 AM)peterbaron_imp Wrote: [ -> ]Bike in NEUTRAL, KILL switch properly set, move side stand couple of times
Do the tach and speedo needles sweep across meters fast or slow upon first ignition on???
What is the battery voltage when IO and when cranking over = will have two different readings , if you are capable of doing this test????
pb
the side stand is good advice but fif its neutral that shouldnt matter?
They seem to sweep like normal.
Unfourtunately i have to catch the subway into work now (11am) and its the MTA so i give myself a little extra time so as to not be late. That means i wont be able to test anything else today.
If anyone in Metro area wants to help me tow my bike to queens i'd be down to buy you some beer [url=http://cb1100forum.com/forum/images/smilies/beerchug.gif\]http://cb1100forum.com/forum/images/smilies/beerchug.gif\
Should be no need.
If both ends of both battery cables are secure, not corroded, then it is very likely a battery issue.
But, best to not buy a new battery until voltage is checked.
If it is actually 12.0 volts, it is 75% discharged and needs charging to test.
If the solenoid chatters, voltage is being supplied to the starter, hence not an issue with being in neutral/side stand switch operating or starter relay functioning.
For those who do not like to click on links (with Sportster specific references deleted):
When the starter button is pressed (key on, off/run switch in run mode), voltage is sent to the coil of the starter solenoid. If the system voltage is normal, the starter engages.
If the system voltage is low, due to low battery or faulty battery cables (the frame/motor end of the negative cable is a common issue), then the voltage may be sufficient to close the coil, but when it closes the high amperage contacts from the battery to the starter, the low voltage has a compound effect:
1. Lower voltage is a challenge to the starter turning over the motor and
2. Lower voltage results in a higher amp draw for the motor to try to pull the same wattage.
For example, a 1.4 KW starter draws 109 amps at 12.8 volts, 111 amps at 12.6 volts , 113 at 12.4 volts, 133 at 10.5 volts, etc.
In a low voltage condition, once the starter tries to draw enough amps to turn over the motor, the voltage drop is so excessive that the coil cannot remain energized and it opens the high amperage contacts to the starter. If the starter button is held, the voltage recovers (after the coil drops out) enough for the coil to again close and the cycle repeats until the voltage drop will not allow the coil to close. This is solenoid chattering.
If the voltage is very low, there is only one click and there is not enough voltage for the coil to again energize.
Why every M/C rider should have a voltmeter/ohmmeter (multimeter) and post voltage values when asking about a problem:
A. Many suspected fuel issues turn out to be electrical.
B. A huge amount of issues are caused by battery cable deterioration and/or loose connections.
Whenever there is a problem that may even remotely be electrical, it would be helpful to post the following voltage readings:
1. KEY OFF battery voltage, at the battery: Normal is 12.8, acceptable is 12.6 (standard lead acid battery, not AGM) to 12.8 for no load. If just taken off a charger, voltage may be 13 point something. The battery needs to sit for a while (or turn key on for a few seconds) before a reading is useful. In the case of a bad cell, the other cells overcharge and give an almost normal reading, until load is applied.
• If lower, then battery is discharged and needs charging or
• Battery has a bad cell
2. KEY ON battery voltage (headlight on): Normal is not under about 12.5 initially, but will decline the longer that the headlight is on, without the motor running. Under no load, 12.5 volts indicates 50% discharge, but under load, it is just voltage drop.
• If lower, then battery is discharged and needs charging or
• Battery has a bad cell or
• Battery cable(s) have high resistance
3. KEY ON battery voltage while cranking: Normal is not under 10.5 volts
• If lower, then battery is discharged and needs charging or
• Battery has a bad cell or
• Battery cable(s) have high resistance or
• Starter is drawing too much current
4. If the bike is running, battery voltage at about 2,500 RPMs should be 13.8 to 14.8
• If not, then check stator resistance and regulator ground
• If the stator is not shorted to ground and resistance is within spec, the regulator or regulator ground is suspect
(06-03-2018, 12:57 AM)Lord Popgun_imp Wrote: [ -> ]Sounds like a typical battery failure. Even a bad one can read 12v with no load. Thats why the above posts are asking about voltage under load.
Bite the bullet and get a new one, or putz around for however long then get a new one 
Reasonable advice, from you, Long Ranger and Klink49, but a caveat to replacing the battery without voltage tests is the possibility that
a. The system is not properly charging or
b. Something is drawing down the voltage with key off
Sportster regulators are energized with key off and some regulator failures can draw down the battery. That was true with Ford systems in the sixties. A warm regulator with a cold engine compartment was a tell.
A quick glance at the CB schematics indicates the is not the case for our CBs, but still proper diagnostics to be sure battery is fully charged, then load test. IMHO, pressing the starter button is an adequate load test, with voltmeter to measure voltage drop under load.