'83 Honda VT500C Shadow.

IN hot weather, the battery goes dry in about 500 miles.
To put in water, I have to take off the seat, remove the battery,
fill it, reverse the process. PITA.

It's my garage sale bike, so it does sit idling a lot while
I'm browsing. The battery does get a workout.

Anything I can do to reduce the water loss or make it easier to fill?
Clever fill gadget? Getting water to it ain't hard. It's telling
when to stop adding water that's hard.

Regulator is at 14.39V. Well within
the 15V max stated in the manual.
I'd crank it down a little if I had the option.

Ideas?
Thanks, mike

On Mon, 19 Jul 2010 17:27:29 -0700, in rec.motorcycles.tech, mike
<(E-Mail Removed)> wrote:

>'83 Honda VT500C Shadow.
>
>IN hot weather, the battery goes dry in about 500 miles.
>It's my garage sale bike, so it does sit idling a lot while
>I'm browsing. The battery does get a workout.

Why do you idle it like that? It doesn't do the bike any good, and probably
annoys everyone else.

>Anything I can do to reduce the water loss or make it easier to fill?
>Clever fill gadget? Getting water to it ain't hard. It's telling
>when to stop adding water that's hard.

All kinds of easy-auto fill gadgets for full size batteries. For lawnmower
batteries, not so much.

>Regulator is at 14.39V. Well within
>the 15V max stated in the manual.
>I'd crank it down a little if I had the option.

14.4? At idle? What's the voltage at cruise RPM? I bet it's way higher
than it should be. Any tendency to burn out a lot of signal lamps and such?
Unless your battery is a complete piece of crap, sustained overvoltage is
about the only way you're going to boil it dry in just a few hours.

--
'82 CB900F
'04 FSC600 (SWMBO)

On Jul 19, 5:27*pm, mike <spam...@go.com> wrote:

> IN hot weather, the battery goes dry in about 500 miles.

How hot are you talking about? Anything over 120 degrees in the
battery area is deadly to lead acid batteries.

> It's my garage sale bike, so it does sit idling a lot while
> I'm browsing. The battery does get a workout.

How old is the battery? Who was the manufacturer?

The best quality flooded cell lead acid MC battery is the Yuasa Sulf-
Stop model.

It has chemistry that attempts to prevent the lead plates from getting
plugged up with sulfur when the battery is discharged.

And that's what you're doing if you let your engine idle while you
shop at the yard sales.

Lead acid batteries are not filled with pure sulfuric acid, the
electrolyte is about 50% water.

When you add water to a battery which is low on water, and run a
current through the battery, it will mix with the sulfur and make more
electrolyte.

But if the sulfur has plated out on the lead plates, it just isn't
available to mix with the water.

So the electric current going through the battery just boils the water
off.


> Anything I can do to reduce the water loss or make it easier to fill?
> Clever fill gadget?

If you have a *small* hydrometer (the floating ball type looks like a
small turkey baster but dorsn't hold much fluid), attach a piece of
1/4 inch tubing to the nipple end. Punch a small hole crossways in
the tubing about 3/8th of an inch from the end.

Fill this device up with distilled water, put the tube into the
battery filler hole and squeeze the rubber bulb.

When you pump excess water from this device into the battery and
overfill it slightly, it will suck the extra water (and some of the
acid!) back out of the battery when you let go of the bulb.

> Getting water to it ain't hard. *It's telling when to stop adding waterthat's hard.

That's why batteries were made with clear plastic cases for many
years. It's harder to tell what the electrolyte level is with the
translucent cases manufacturers have been using

> Ideas?

Your best bet is to buy a sealed maintenance free battery.

And quit idling the engine so much.

Mark Olson wrote:
> mike wrote:
>> '83 Honda VT500C Shadow.
>>
>> IN hot weather, the battery goes dry in about 500 miles.
>> To put in water, I have to take off the seat, remove the battery,
>> fill it, reverse the process. PITA.
>>
>> It's my garage sale bike, so it does sit idling a lot while
>> I'm browsing. The battery does get a workout.
>
> There's absolutely no reason to leave your bike running while
> you spend time at garage sales.

Sounds like you haven't done the math.
Start a bike 50 times a day and something that was designed to
last for many years doesn't last nearly that long.


But that is irrelevant to
> the problem you describe, other than it may expose your battery
> to unnecessary amounts of heat.
>
>> Anything I can do to reduce the water loss or make it easier to fill?
>> Clever fill gadget? Getting water to it ain't hard. It's telling
>> when to stop adding water that's hard.
>
> You're trying to fix the wrong problem.
>
>> Regulator is at 14.39V. Well within
>> the 15V max stated in the manual.
>> I'd crank it down a little if I had the option.
>
> The battery is being overcharged. Either the regulator is
> defective or the sense line (common on Hondas) is sensing
> the wrong voltage, causing the regulator to set the output
> voltage of the alternator too high. Fix the connection
> problem(s) or replace the regulator. Simply replacing the
> regulator won't fix the problem if it's a connection issue.
>
> I've seen this exact problem on at least two early 80s
> Hondas and fixed them both the same way.

Good call.
Rerouting the sense line did drop the voltage.
Should know in a week if it fixes it.
All I gotta do is remember to charge it a few times
over the winter.

My jaw is getting tired from all the bubble gum I'm
chewing to keep this thing patched up.
If I could find a 500cc water-cooled, shaft-drive
bike, I'd buy a new one. they don't make 'em
like they used to.

thanks, mike







The problem is that
> the Kelvin sense wire goes through the ignition switch, which
> has a fair amount of voltage drop through multiple connections
> on an older bike with oxidized connections. So the regulator sense
> line is seeing about 1V less than what the battery sees. The
> fix is to either clean and/or replace all the tired connections
> or re-route the sense line directly to the battery. If you
> choose the latter option you need to ensure the sense line
> doesn't draw excess current with the bike not running or it
> can drain the battery quickly. In both cases I verified this
> with a sensitive milliammeter before committing to the fix.
>
>

` <(E-Mail Removed)> wrote:

> How old is the battery? Who was the manufacturer?

<Snip> and Krusty misses the problem again.


--
BMW K1100LT Ducati 750SS Triumph Street Triple Honda CB400F
Suzuki TS250 Suzuki GN250 chateaudotmurrayatidnetdotcom
Nothing damages a machine more than an ignoramus with a manual, a
can-do attitude and a set of cheap tools

mike <(E-Mail Removed)> wrote:

> Regulator is at 14.39V. Well within
> the 15V max stated in the manual.
> I'd crank it down a little if I had the option.

As others have said, if it's kicking out well over 14v at idle (which I
presume is where you measured it), it'll be kicking out more higher up
the rev range. Sounds like the reg/rec is dead and/pr the connections to
it are corroded and dying.

Never heard of the sense line thing, but I'll defer to Olson on matters
electrical.

If Mark's fix doesn't work, then you'll have to replace the reg/rec[1].
And replace the battery too.

[1] Just had to do this (well, under warranty, so the dealer did) on my
Ttriump Street Triples.



--
BMW K1100LT Ducati 750SS Triumph Street Triple Honda CB400F
Suzuki TS250 Suzuki GN250 chateaudotmurrayatidnetdotcom
Nothing damages a machine more than an ignoramus with a manual, a
can-do attitude and a set of cheap tools

Mark Olson <(E-Mail Removed)> wrote:

> Look up Lord Kelvin...
>
> http://en.wikipedia.org/wiki/Four-terminal_sensing

<Snip interesting stuff>

Thanks for that. Like I've said before, electrickery really isn't my
strong suit. I've only had four bikes (I think) over the decades with
duff charging sytems.

One was a Suzuki GS250 with a typically crap Suzy late 1970s-early 1980s
charging system and that fried the alternator and reg/rec.

Then there was a Suzuki TS250 dirt bike whose connections to the tiny
little solid-state reg-rec had corroded badly. The Yamaha 660 Tenere
which had the same ailment and died on the way back from last year's
Elefant, and was abandoned in Germany with a wonderfully cooked
alternator and wiring loom.

And finally, the modern Triumph whose reg/rec just surrendered after
2000 miles, and whose reg/rec has apparently been replaced with a unit
that "has greater longevity", according to the dealer. In other words,
the old one wasn't any good.


--
BMW K1100LT Ducati 750SS Triumph Street Triple Honda CB400F
Suzuki TS250 Suzuki GN250 chateaudotmurrayatidnetdotcom
Nothing damages a machine more than an ignoramus with a manual, a
can-do attitude and a set of cheap tools

"WW" <(E-Mail Removed)> wrote in message
news:j_adna1Pr-(E-Mail Removed)...
>
> "mike" <(E-Mail Removed)> wrote in message
> news:i22qi7$s3s$(E-Mail Removed)...
>> '83 Honda VT500C Shadow.
>>
>> IN hot weather, the battery goes dry in about 500 miles.
>> To put in water, I have to take off the seat, remove the battery,
>> fill it, reverse the process. PITA.
>>
>> It's my garage sale bike, so it does sit idling a lot while
>> I'm browsing. The battery does get a workout.
>>
>> Anything I can do to reduce the water loss or make it easier to fill?
>> Clever fill gadget? Getting water to it ain't hard. It's telling
>> when to stop adding water that's hard.
>>
>> Regulator is at 14.39V. Well within
>> the 15V max stated in the manual.
>> I'd crank it down a little if I had the option.
>>
>> Ideas?
>> Thanks, mike
>
> You can add a 10 amp diode in series with the charging wire to the battery
> and this will drop the voltage about 7/10th of a volt. Get polarity
> correct of course. WW

And move the regulator's voltage sense wire to the junction of the added
diode's anode and the regulator's output wire, otherwise the regulator will
just compensate for the diode voltage drop (if this causes the regulator to
become erratic, you may have to add an electrolytic capacitor at the same
point as the sense wire).

Seems to me it would make more sense to fix the fault properly rather than
bodge it and hope for the best.

14.4V should be regarded as the absolute max charging voltage, it would be a
good idea to check if it rises above that with the engine held at 5000revs
for a few minutes.

As someone else mentioned, cheap shitty batteries tend to gas off their
electrolyte for no good reason.

On Jul 20, 4:04*am, totallydeadmail...@yahoo.co.uk (Pup Tent Peter
Puffer) wrote:
> ` <breoganmacbr...@yahoo.com> wrote:
> > How old is the battery? Who was the manufacturer?
>
> <Snip> and Krusty misses the problem again.

Hey, Peter Puffer!

Did ewe ever attend a military technical school that trained you to
troubleshoot and repair aircraft and missile electrical power systems?

I did.

Did ewe ever get paid to work on lead acid batteries full time?

I did.

Did you ever attend a civilian technical school that trained you to
operate high voltage power transmission and distribution systems?

I did.

Have you ever operated gasoline, diesel, steam and gas turbine power
generators?

I did.

Did you ever install a battery in a manned spacecraft?

I did.

Now tell me I don't know what I'm talking about, you slimey limey
cocksucker!

BTW, I guarantee that Mike, the OP, will be replacing his sulfated
flooded lead acid battery in the next 18 months...

"`" <(E-Mail Removed)> wrote in message
news:be5bb928-7d7b-4342-97ec-(E-Mail Removed)...
On Jul 20, 4:04 am, totallydeadmail...@yahoo.co.uk (Pup Tent Peter
Puffer) wrote:
> ` <breoganmacbr...@yahoo.com> wrote:
> > How old is the battery? Who was the manufacturer?
>
> <Snip> and Krusty misses the problem again.

Hey, Peter Puffer!

Did ewe ever attend a military technical school that trained you to
troubleshoot and repair aircraft and missile electrical power systems?

I did.

Did ewe ever get paid to work on lead acid batteries full time?

I did.

Did you ever attend a civilian technical school that trained you to
operate high voltage power transmission and distribution systems?

I did.

Have you ever operated gasoline, diesel, steam and gas turbine power
generators?

I did.

Did you ever install a battery in a manned spacecraft?

I did.

------------------

Was that the one that blew up on the launch pad?