Charging Issue

[REO Scorpio]

Been awhile since I've been on. Hope you're all well.

I've poured through some of the stickies on the topic, but I wanted to solicit some thoughts on my current charging situation.

FYI, I have a PCV and autotune on there, as well as BD-43s headlight mod.

Mine is an '09, had since new. Replaced the first Yuasa battery about six years after purchasing as it was losing charge pretty quickly.

I've had two replacement batteries since. Both work fine for a season, but then die out completely. Earlier this week, I had it die completely to the point where I couldn't even bump start it, though I had just ridden it about twenty minutes before.

Got a new Yuasa battery yesterday. Charged it up overnight on the optimate.

Today, I went out there with the tank off to do some measurements.

Sitting, key off, its at 12.9
Sitting, key on, its roughly 12.7
Started at 4K, its at 13.54

Measured the voltage from the rectifier when running at idle and is was 13.18. Will have to test again at 4K

Measured the resistance from the stator wires, but this is unreliable as my dmm seems to suck at ohms. Each time I touch the probes to find my base I get a different number. The one time it was consistently .7 on the meter with the leads together, I got .4-.5 on the various pairs of wires after subtracting. Wish I had a better meter.

Leakage test on the new battery showed no draw.

Does this sound like a rectifier issue at this point as it's not getting close to 14v under load? Any luck finding a quality cheap ebay part?

Thanks!

Scorp

 

[TownsendsFJR1300]

Charging voltage is a bit low.

Re your questions, Motogiro will chime in.


Just as an FYI, here's a video of mine (cold start, also BD43 mod) to get an idea of voltages:

https://www.flickr.com/photos/147134237@N06/29303851750/in/dateposted/


*Battery was JUST charged as it was due for replacement-notice the drop to 10 volts with initial cranking..

 

[REO Scorpio]

Thanks, Townsends. I had seen that.

Mine new battery drops to about 11.5 on crank.

The first battery lasted so long, but since, have gone through two spares and now this one. Just seems to be burning them out.




Sent from my iPhone using Tapatalk

 

[TownsendsFJR1300]

[MENTION=2579]Motogiro[/MENTION]

Cliff should be able to answer your questions (I hate electrics)..

 

[Motogiro]

When the battery is at low voltage or potential and first being charged the internal resistance is low which creates a greater load on the system which will show lower voltages. This means that some voltage measurements although normal for a fully charged system would be correct but for a system with a sick battery or low charge battery will show different voltages because of that internal load.
I recently needed a new battery and went to a dealership to purchase one because the dealership was the only place that had the battery for my bike. I was very wary because the person brought out the battery pretty quickly but thought maybe I was just being too cautious. As it turns out the battery was a Yuasa and has not performed anywhere near where an off brand battery I had which had lasted for like 7 years. The voltages are well below what the norm would be. The cranking seems to be good and I have been very busy with other duties which have bitten into any riding of late.
Other possibilities could be the quality of the product. I've read about this with watch batteries. It may be as simple as a brand loyalty problem. Many of us trust the quality of a product by it's brand but the way it works today is changing. Since a battery should come to service in a specific way you may get one that has come to you from a person who lacks experience and is tired from cutbacks where they have to wear different hats all day.
They are not bad people and our volt meter may not have a setting on it that tells when we've been cheated by the circumstances. Although that might be a great new feature!

Square 1. Charge the battery and load test it. Voltage tests are great but they are nominal in the sense that that we can see different voltages with a partially charged battery. A battery can spin that starter properly if it has a good depth of charge even though voltage may show lower than average. Today voltage measurements are good reference points because we have pretty accurate multimeters and the science of chemistry and manufacturing are pretty close as far as standards.
You may just have another bad battery. Charge it and load test it. If it's bad replace it and then check your voltages. If it's good you may have a an open diode in the R/R or a stator problem. When you did your stator test did you test each leg against ground?

Thank you for the ping Scott!

 

[REO Scorpio]

Thanks for the info. And yes, I did test them against the chassis ground as well.

this is now the 4th battery. I replaced the stock battery with a relatively cheap one from amazon. The third battery was more expensive but only lasted one season. I charged this new one up and it is running fine thus far.

It is simply that the charging system just simply doesn’t seem to get enough to it. I feel that over the long run, this has led to degrading the quality of the batteries.

I tested the volts from the stator wires (white) at the clip and they were all 30 at idle and climbed to 60 at 4K. They were pretty dead even.

But I don’t trust the ohm reading nor the diode test on my multimeter. The diode test on the actual rectifier just showed 194 no matter what combination I touched including the air.

As for testing the ohms from the static connector , it just reads whatever the value was when I touch them together to account for that error.

It’s a cheap innova 3310 so may need to get a replacement.

Is there another test I can run on the stator or rectifier that I’m not seeing?


Sent from my iPhone using Tapatalk

 

[REO Scorpio]

Just an update. I replaced the leads and fuse in my dmm and used some cleaner on the battery leads.

Tested the ohms from the stator. The new leads had a resistance of .2-.3, and all combos came in at .6 or .5. So the stator looks good, with the voltages when running from earlier.

Then pulled the rectifier and checked the diodes, going through all of the options. Open line on all when nevessary, and all at 501, 500, 499 on the others. So that looked good.

Started the bike and measured the volts from the plug into the rectifier. At 4K, it was putting out 14.17. That still seems low to me, although I think the spec is 14.1-14.9.

Charged and off tender, new batter was 12.92. With key on, went down to 12.81. Cranks at 11.51.

Cranked to 4k, it was at 13.75.

​

Ran leakage test with the fixed dmm and it was .265. Could be from the PCV/Autotune.

I know I should get it load tested even though it is brand new, but based on those tests, the numbers look right.

 

[TownsendsFJR1300]

Your charging #'s are fine. Mine has NEVER hit 14 volts, usually 13.9 tops or so...

Cranking voltage is fine too.

Also, (FYI, you may already know), brand new batteries should be put on a tender (1.25amp is fine) PRIOR to use. The battery, with acid just added is about 80% charged.

Putting it on the charger BEFORE any load will extend the life of the battery. That usually takes 6-8 hours...

 

[REO Scorpio]

Yeah, I had it on charger overnight before I started messing with it.

I'll just keep an eye on it for now. Haven't ridden since it died on me.

Thanks!

 

[Motogiro]

Ran leakage test with the fixed dmm and it was .265. Could be from the PCV/Autotune.

Your leakage test looks high. Generally .02 is acceptable and on an automotive battery with higher amp capacity maybe .1 I would say you should look for a parasitic draw. Hook up you meter, then touch the battery lead to it's post to allow all capacitors to charge. Then pull the lead off to measure any parasitic draw on your meter.

 

[REO Scorpio]

I followed the leakage test from the Haynes. Pull negative battery lead, tough positive lead from meter to it, and then put the negative meter lead to the post.

Would that give me different results than what you are describing?

 

[Motogiro]

I followed the leakage test from the Haynes. Pull negative battery lead, tough positive lead from meter to it, and then put the negative meter lead to the post.

Would that give me different results than what you are describing?

Hook the test meter between the battery terminal and the battery lead, as if you are doing the test. Then touch the battery lead to the battery terminal while keeping the meter attached. This will allow capacitors to charge. When you detach the battery lead and battery terminal from each other with the meter still attached, the meter will measure the true draw. If not done properly you may be measuring capacitors in electronics that are charging which is not true parasitic draw.

 

[REO Scorpio]

Hook the test meter between the battery terminal and the battery lead, as if you are doing the test. Then touch the battery lead to the battery terminal while keeping the meter attached. This will allow capacitors to charge. When you detach the battery lead and battery terminal from each other with the meter still attached, the meter will measure the true draw. If not done properly you may be measuring capacitors in electronics that are charging which is not true parasitic draw.

Ok, so when I did this I got a reading of .001 lol


Sent from my iPhone using Tapatalk

 

[Motogiro]

Ok, so when I did this I got a reading of .001 lol


Sent from my iPhone using Tapatalk

Excellent!

 

[REO Scorpio]

Excellent!

Any theories on why the voltages are low from rectifier and to the battery?


Sent from my iPhone using Tapatalk

 

[Cali rider]

If you find that you need a replacement rectifier I have one available.

 

[Motogiro]

Any theories on why the voltages are low from rectifier and to the battery?


Sent from my iPhone using Tapatalk

What voltages are you getting now? Is you meter accurate?

 

[REO Scorpio]

I believe my meter is now more accurate. I’m getting 13.73 v at the battery when revved to 4K.

At the rectifier, it’s 14.17


Sent from my iPhone using Tapatalk

 

[Motogiro]

I believe my meter is now more accurate. I’m getting 13.73 v at the battery when revved to 4K.

At the rectifier, it’s 14.17


Sent from my iPhone using Tapatalk

You're golden! Go ride!

Sent from Moto's Motorola

 

[ShoopCE]

Any updates? Still riding? :thumbup:

I was having similar problems, similar meter readings. I think my problem was fixed by cleaning the leads that connect to the battery.

My bike wouldn't start the week before last. I had a dry AGM replacement battery sitting in the garage since 2015, so I loaded up the acid and charged it overnight. The bike ran fine over the weekend. But then it died again on Monday. So I did all the suggested tests. Everything was close but the voltage at 4k rpm was a bit below 14.

So while I was under there, not hurried like I was first time, I cleaned up the leads' contacts w steel wool. They were slightly oxidized.

Since then the bike has run and started like a champ for the past two weeks. I charged up the old battery and took it to Autozone. It tested fine under load. It was 10 yrs old, but I hate to recycle it.

Chris