Volts ok ??? or what !

[Chromedome]

Hi guys an Gals, iv been out today on the 82 GS 1100L first time this year and with a new battery, "Yuasa YB14L-A2" 100++ miles, still cool enough yet, anyhow, popped the seat and checked the voltage immediately we got home, got a reading of 12.67 volts, id expected 14v+ possibly 14.4v. Its been on a new Motobatt trickle charger ever since about 5 hours now an still reading 12.67v. iv checked the charger, its reading 14.7v. It had been on the charger for a few days before this and when we left this morning was reading over 12v, not sure exactly. Confuseing or is it just me ! any help would be great, Good Luck and thanks.

[BassCliff]

Hi,

Check the charging system. Go through the Stator Papers and the accompanying documentation developed by Mr. posplayr. You'll find links on my website in the READ ME page and in the electrical section. Clean the wiring connections and grounds, all of them. Run the ground wire from the r/r unit directly to the negative terminal of the battery.

Thank you for your indulgence,


BassCliff

[terrylee]

Check out the Stator Papers on Basscliff's site, will tell you all you need. But unless your bike is running when you're testing it, your reading sound about right, might go up to 12.8 sometimes. terrylee

[Killer2600]

That's perfectly normal and nominal voltage for a sitting battery that's fully charged.

Worry not and go ride some more

[posplayr]

If you had recorded the voltages during a Quick Test then a reasonable assessment of the charging system could have been made.

As is who knows.

[AJ]

12.67 is a fine rest voltage reading for a 6-cell lead acid battery.

Start the bike, put the voltmeter on the battery, and take readings at idle and 2500rpm. If you're above 13.5V at 2500, then your your bike is charging the battery and all is well with the world.

[posplayr]

12.67 is a fine rest voltage reading for a 6-cell lead acid battery.

Start the bike, put the voltmeter on the battery, and take readings at idle and 2500rpm. If you're above 13.5V at 2500, then your your bike is charging the battery and all is well with the world.

Not necessarily. I have found it necessary to test at 5000 RPM as well as what often happens the voltage will drop when moving from 2500 to 5000 RPM. Not always but 25-30% of the time. This is a direct indication of excessive resistance between the R/R and battery.

Quick Test Steps:

1.) key off................Normal 12.7 volts-12.9 volts

2.) key on (but not cranking with lights for 10 sec).....Normal 12.2-12.5 volts

3.) at idle (1500 rpm).....12.6volts - 13.2volts

4.) at 2500 rpm 13.5 -14.0 volts

5.) at 5000 rpm.....14.0 -15.0 volts

6.) key off.....slightly higher than measurements # 1 (12.8-13.0 v)

QUICK TEST Diagnosis Summary:

Basically Step #1 and #2 is making sure the battery is charged and in good health. The drop should be about 0.5 volts for normal headlamp and coil load (without cranking the starter). Anymore than 0.5V drop indicates the battery is weak even though the static voltage is OK (12.7-12.8V)

Step #3 is get a baseline starting voltage. This will vary some depending upon your idle and the particular R/R you have. It could be lower than the off voltage or as you idle up it will increase to 13.0 v

Step #4 by the time you get to 2500 RPM you should have close to the maximum output voltage even if you have bad connections. You are not pushing as much current and this shows that the stator is likely good.

Step #5 by the voltage at 5000 RPM being higher than at 2500 RPM you have a pretty good indication that your connections are good. If the voltage at 5000 drops from 2500 you have bad connections. If you already checked the grounds then it is likely in the positive legs between R/R(+) and Battery (+) check fuse box and the large bullet connector to the battery. The voltage climbs above 15.0 V it is likely the R/R not regulating and is bad.

Step #6 If after running for a few seconds in a charging state the voltage to the battery should have risen a bit. If it is lower than where you started then you did not charge at all, Again this will vary some what depending upon how long you let the bike run.

[Chromedome]

Hi again, took a while today and went through pretty much all the possible connections both positive and negative and now everything seems to be working A ok, as it should, iv no idea which was the offender but important thing is, next good day "were on the road again" thanks again folks, Stephen.




Everyone in Ireland has friends in America,
But not everyone in America has friends in Ireland.

my grannie said it.

[posplayr]

Hi again, took a while today and went through pretty much all the possible connections both positive and negative and now everything seems to be working A ok, as it should, iv no idea which was the offender but important thing is, next good day "were on the road again" thanks again folks, Stephen.




Everyone in Ireland has friends in America,
But not everyone in America has friends in Ireland.

my grannie said it.

you should really test with the revised Phase A tests procedure to insure you really got all of the connections. It only takes 0.1 ohms to ruin your day.

Link to Revised PHASE A of Stator Pages:

http://www.keepandshare.com/doc/3970459/stator-papers-phase-a-pdf-may-13-2012-10-43-am-55k?da=y

ORIGINAL_STATOR_PAGES

The most important thing to do checks at 5000 RPM which is typical cruising speed. You might find that you will need to clean your fuse box to get the positive side voltage drops below 0.2V at 5000 RPM. In steps #1 above you should of gotten most of the connections between the R/R(+) to battery (+) in good shape except the fuse box.