81 GS850GX Battery Drain Problem

[Buster-boy]

Battery drains after about 10 minutes of riding. Bike dies. Reads 12.5v prior to ride, 11.*v when dead. Battery is a new Yuasa, stator and rectifier are brand spankin new (installed them myself), all wire connections are good (boy that sucked tracing them!!), negative battery cable/engine ground has been replaced as well.

All electrical works just fine HOWEVER I noticed my fuel gauge doesn't work. I jumpered the gauge on the instrument panel and it went from E to F so we're good there.

I tested the tank unit with an ohm meter. Clymers says it should read 118ohms max. It read 123+/-. Since this unit is obviously bad, and one of the two wires is the black/white ground wire, would this cause the battery to drain, or if the wires were just disconnected would it cause the drain?

If so, besides replacing the unit, what can I do to get around this issue?

[Dogma]

Is it a sealed AGM battery or a regular vented liquid one?

[Buster-boy]

Battery Drain

It's a Yuasa liquid vented battery

[Dogma]

I seem to remember that there is preparation you have to do to those before you can use them. "Priming" or some such. What I remember is that they won't hold a charge until you do this. Did you do anything like that to it?

[BassCliff]

Hi Mr. Buster-boy,

If the battery was not properly initialized the performance can be adversely affected. What were the readings of the Stator Paper tests after you installed the new stator and r/r? Did you connect the r/r ground directly to the negative terminal of the battery? Does your r/r have a sense wire? If so, where is it connected? Have you had a chance to check and clean every electrical connection on the entire harness? Keep us informed.


Thank you for your indulgence,

BassCliff

[Buster-boy]

Priming

Dogma, can you explain what that is - Priming? All I can tell you is I stopped by the store and bought it. I asked if it needed filled and charged. They said it was already charged, so I took their word for it.

[rustybronco]

Battery drains after about 10 minutes of riding. Bike dies. Reads 12.5v prior to ride, 11.*v when dead...

All electrical works just fine

I think you need to re-think this statement.
if the battery drains after 10 minutes of riding, she ain't charging...

what are the battery voltage readings at idle and 5k rpm's?

[flyingace]

Dogma, can you explain what that is - Priming? All I can tell you is I stopped by the store and bought it. I asked if it needed filled and charged. They said it was already charged, so I took their word for it.

Alway check the voltage of the battery before you install it. It should be 12.7 volts or so or I would charge it first.

It's possible your battery won't hold a charge, but that seems less likely than a problem with the charging system. I agree with the other poster, determine your charging #s at idle and 5K.

[Steve]

Personally, I don't care if they tell me "it's ready to go", I perform the initialization procedure.


.

[Dogma]

Dogma, can you explain what that is - Priming? All I can tell you is I stopped by the store and bought it. I asked if it needed filled and charged. They said it was already charged, so I took their word for it.

Everybody else has it... Initializing. I knew it was something like that.

[Buster-boy]

Battery Drain

Actually, I shouldn't say it's "New". I bought it new back in May from IronPony but I've had so many issues with this bike I've only gotten 30 miles or so on it. So yeah, I guess you could say it's a "new" battery. It's been charged a billion times since then. In fact it's on the charger now cuz I killed it about an hour ago.

The stator and R/R ARE new as of about 3 weeks ago. Once I get the the battery charged and the bike running again (probably tomorrow) I'll check the v's at 5k rpm at post it here.

The negative cable on the battery was all junked up and theterminal was loose, so I installed a new one today. Someone had suggested I try that as well thinking maybe I had a bad ground. Haven't tested that yet cuz battery is dead.

I'll keep posting as things unfold.

Thanks guys!! Very appreciative!!

[Steve]

If you read the initialization procedure I linked to above, you will see that one of the quickest killers of a battery is to use it to start a bike or car before fully, properly charging it. By starting with a heavy drain, you set its maximum at considerably less that its designed potential. Fortunately, even a reduced-capacity AGM battery usually exceeds a good wet-cell battery, so many don't even know what they are missing.

.

[Buster-boy]

Battery Drain

You know that's interesting. Since you don't have to do this with car batteries I guess I figured MC batteries were the same. I bought another Yuasa battery from the same place a year ago for another bike I owned. At that time they said I had to wait 24hrs to pick it up. They had to fill and charge it becuase they're shipped and stored dry. So, when I bought this battery they just handed it over. That's why I asked if it needed charged overnight and they said nope it's already charged. I thought that was a little strange, but I figured they're the experts.

Now, I've charged this battery a hundred times since buying it. When done charging, my voltmeter reads 12.5*v. Assuming this battery was never initialized, am I now good since I've charged it so many times, or should I get a new one and start from scratch?

[Buster-boy]

Battery Drain

Ok here's the numbers -

At an idle - 12.0v
At 5000rpm - 13.20v
Drove 6 houses up the street, turned around, bike died.
Tried to restart until battery out of juice, pushed it home
Next reading says - 11.98v
Let sit 5 minutes - 12.08v
Tried to restart until battery out of juice - 11.63v
Let sit 5 minutes - 12.00v
Tried to restart until battery out of juice
Back on charger
Came inside to update this thread

Keep in mind it has new stator, R/R,(three weeks ago) newer battery (May of 2009 w/approx 2 hours usage on it)

It's on the charger now. Next time I'll drive til it dies but this time I won't try to restart it. I'll push it home and take another reading. I thinking there's a chance it's a carb/fuel issue and I'm killing the battery trying to restart.

[Dogma]

Those numbers sound low, but the voltages really need to be taken on a fully charged battery. Please get some numbers when it's fresh off the charger. For methodical diagnosis, we need to establish that the battery and charging system are good before trying to diagnose possible fuel/carb/valve clearance issues. Especially since a weak battery can cause hard starting due to weak spark.