Charging System QUICK TEST

[posplayr]

EDIT 8/10/2016: Make the measurements by stabbing the center posts of your battery. These are direct battery measurements. Avoid any connections.

EDIT 2/27/2014 : Read about the latest SERIES R/R's that are available
Stator Pages

Sometime people get a little confused in the details of doing the stator pages and sometimes they forget to check their battery. So just to help things along if someone is a bit confused and needs a sanity check.

These tests are NOT mandatory as long as you know you have a good battery and can follow your way through the stator pages. Otherwise it is just a nice real quick test.

NOTE THIS IS NOT TO REPLACE THE STATOR PAGES. IT IS JUST A QUICK FIRST SANITY TEST TO see the battery is good enough to proceed with the STATOR PAGES. The first part of the stator pages will actually measure how good your connections are and goes well beyond this QUICK check.

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). If your battery is any lower it can have an effect on your charging voltages as the charging system only has so much capacity and will be drug down by a poor battery.

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 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.


Good Luck


P.S. The voltages are indicative of state of charge as described in the file below. There are some variations in voltage but the shape of the curves is pretty representative.

http://www.scubaengineer.com/documents/lead_acid_battery_charging_graphs.pdf

Rule of thumb C/10 would have the R/R output set at 14.V/100% SOC which is pretty typical. The Suzuki R/R's are pretty loosey goosey with an upper allowable range of 15.5V IIRC.

Anyway, this is really relatively independent of the at rest battery voltage which is not really even given in the curves as they assume at least C/100 Charge / Discharge and there is a significant discontinuity there.

Taking a closer look at the last chart is showing 12.7V at C/100 discharge and 13.35 ish at C/40 charging. So the lower chart confirms voltages in high 12's even possibly over 13V for topped off batteries.

So immediately after a ride if you are are at 12.5V I would say you are probably not charging very well.

[bwringer]

Good info, and this aligns quite well with my experiences.

Works for cars, too!



I like to watch the (digital) voltmeter "count down" for 30 seconds or so when the key is on but before I start the bike. With the load of the lighting and such, you'll see a healthy battery count down at a reasonable rate -- maybe .02 volts per second -- enough time to discern each 1/100th volt -- and then the rate of loss will quickly slow down and stabilize. With an weak or unhealthy battery that reads OK at rest, the rate of loss is much higher under a load. Unscientific, but you can get a rough idea of the battery's condition this way.

Voltage while cranking is tough to measure accurately (some voltmeters just show a blur of digits), but a healthy battery (and healthy starter, etc.) will usually stay above 12V. Anything below 11.8V is pretty marginal, and below 11V might not fire the coils. On a GS with decent carburetion, you really don't get a chance to measure cranking voltage, since the engine will fire immediately.

[posplayr]

Good info, and this aligns quite well with my experiences.

Works for cars, too!



I like to watch the (digital) voltmeter "count down" for 30 seconds or so when the key is on but before I start the bike. With the load of the lighting and such, you'll see a healthy battery count down at a reasonable rate -- maybe .02 volts per second -- enough time to discern each 1/100th volt -- and then the rate of loss will quickly slow down and stabilize. With an weak or unhealthy battery that reads OK at rest, the rate of loss is much higher under a load. Unscientific, but you can get a rough idea of the battery's condition this way.

Voltage while cranking is tough to measure accurately (some voltmeters just show a blur of digits), but a healthy battery (and healthy starter, etc.) will usually stay above 12V. Anything below 11.8V is pretty marginal, and below 11V might not fire the coils. On a GS with decent carburetion, you really don't get a chance to measure cranking voltage, since the engine will fire immediately.

There is nothing unscientific about measuring the voltage loss per second. It is a little more complicated and I was trying to keep it simple. The ranges are based on what I'm seeing on my GS1100ED so YMMV.

I really would not want to judge battery state for how low the voltage is pulled during cranking with just avolt meter. However this is pretty much exactly how you measure the batteries internal resistance which is a direct measure of state of charge. An O scope with a current clamp helps alot but again trying to keep this very simple.

I think on my ED i see the LED voltmeter flash into the 10's on cranking

[1980GS1000E]

And the best place to check the voltage is at the starter relay?

[posplayr]

And the best place to check the voltage is at the starter relay?

For this crude test I don't think it matters too much but the closer to the battery the better. If we were doing the Stator pages you would be more specific.

Solenoid and a ground would be perfectly adequate as there is no current flow so no voltage drops

[cableguy]

posplayer, I like your mantra "I'm trying to keep things simple" LOL! Your struggle is evident and appreciated, as you get way over the heads of many then reign it back. Not bustin just sayin.....it's all good stuff and thanks for taking the time with a noob like myself. I have the aptitude just not the experience, and I bet there are many others like myself.

[posplayr]

posplayer, I like your mantra "I'm trying to keep things simple" LOL! Your struggle is evident and appreciated, as you get way over the heads of many then reign it back. Not bustin just sayin.....it's all good stuff and thanks for taking the time with a noob like myself. I have the aptitude just not the experience, and I bet there are many others like myself.

To me simple enough is to be competent fixing your own or someone else's bike. That also means knowing enough to steer away from some of the more unusual diagnosis techniques . Obviously this is a challenge drawing a clear line, and there is always someone wanting to be a smart@$$.

If you can follow the directions to get past the basic stuff, then the more experienced guys can have some enjoyment trying to tackle the more interesting problems .

A 100 post thread on a dead battery is not very entertaining

[cableguy]

huh. Not sure if I ticked you off or not, but didn't mean to. Maybe I'll keep my mouth shut with the simple stuff for a while. All I wanted to say is thanks for the effort to dumb it down for us dummies.

[posplayr]

huh. Not sure if I ticked you off or not, but didn't mean to. Maybe I'll keep my mouth shut with the simple stuff for a while. All I wanted to say is thanks for the effort to dumb it down for us dummies.

No, just lamenting a little

I'm learning that if it is not "entertaining", I'll just let it pass.

[Do Little]

You know what else would be great, a guide to using a voltmeter as related to a motorcycle. Like explaining what systems use what voltage and what to look for when testing differnt systems and how the settings work. All I ever see is "turn it to this and test," and my voltmeter never seems to have the exact setting specified, and I don't really understand voltmeters so I don't trust myself to improvise. Or links to some good articles on the subject would work as well.

[posplayr]

You know what else would be great, a guide to using a voltmeter as related to a motorcycle. Like explaining what systems use what voltage and what to look for when testing differnt systems and how the settings work. All I ever see is "turn it to this and test," and my voltmeter never seems to have the exact setting specified, and I don't really understand voltmeters so I don't trust myself to improvise. Or links to some good articles on the subject would work as well.

You would be best to read the manual for your own device. Basically it will

• read a DC Voltage
• read a AC Voltage
• read a DC Current
• read ohms

Look in the manual for those sections. If you still need something more general search Google but your manual should be your main refererence. as there are differences between digital and analog meters and the specific settings for automatic v.s. manual settings.

[koolaid_kid]

You know what else would be great, a guide to using a voltmeter as related to a motorcycle. Like explaining what systems use what voltage and what to look for when testing differnt systems and how the settings work. All I ever see is "turn it to this and test," and my voltmeter never seems to have the exact setting specified, and I don't really understand voltmeters so I don't trust myself to improvise. Or links to some good articles on the subject would work as well.

There are many explanations out there, including videos:

http://www.google.com/#hl=en&sugexp=lcms&xhr=t&q=using+multimeter&cp=12&pf=p&sclient=psy&site=&source=hp&aq=0&aqi=&aql=f&oq=using+multim&pbx=1&bav=on.2,or.r_gc.r_pw.&fp=95cbfeec40b28ccc&biw=1639&bih=886

The biggest problem is there are also lots of different types of multimeters out there. Dials (a.k.a. analog) are all but obsolete, but you can still find them if that floats your boat. There are also clamp-style current meters, but their other functions appear to be limited in range (for the most part). Auto-sensing multimeters are also out there, although I have not personally used any. The most common are your standard digital readout multimeters.
I would select a couple that show digital multimeters of your type and read, then watch a video or two.
Hope this helps.
(You posted whilst I was researching, Jim, but this might help him a bit.)

[TPL]

You know what else would be great, a guide to using a voltmeter as related to a motorcycle. Like explaining what systems use what voltage and what to look for when testing differnt systems and how the settings work. All I ever see is "turn it to this and test," and my voltmeter never seems to have the exact setting specified, and I don't really understand voltmeters so I don't trust myself to improvise. Or links to some good articles on the subject would work as well.

A multimeter is very easy to use, Many have an "auto" setting that you can start with. read the lit you get with it and understand the difference between alternating current and direct current. Ohms is simply the amount of resistance and effects the flow (amps) of current. Think of a straw with water flowing through it, squeeze the straw a bit and the flow slows down, that is resistance and the same is true with electrical systems. Your stator puts out raw alternating current AC, the Rectifier circuit within the R/R converts the AC to the usable DC, direct current that the bikes systems run on.

[jamie furman]

thanks will give it a try, but even if that is the problem why the loud noise? I have other GS's that even when the battery is almost dead they barely crank and then click but don't make that loud metallic noise.

[posplayr]

thanks will give it a try, but even if that is the problem why the loud noise? I have other GS's that even when the battery is almost dead they barely crank and then click but don't make that loud metallic noise.

Which thread are you posting to?