Battery Box Question ... - Page 3

 


Actually, I have push-started this particular motorcycle before.  I had my
starter switch wiring fail.  It took quite a bit of work, but it was very
doable.  So even without a kick starter, I'd probably get it going.

On the night in question, the starter wouldn't work and the gal I was with
advised me that the headlight also wasn't working.  I assumed a blown fuse
and assumed that maybe the ignition was still active, so I push-started it
in the parking lot.  It took some huffing and puffing, but I got it started.

So me and the gal got on this headlightless bike and were weaving down an
unlit country road kind of bouncing back and forth between the center line
and the edge of the road.  The tail light and the turn signal lights (so I
was visible to traffic) were still working.  Finally I got a car behind me
that gave me some illumination, and I was good to go.

Then the Marshall police spotted me and pulled me over.  I pulled on a side
street for my own safety and stopped with them behind me.  I didn't want to
stop the engine so I stayed on the motorcycle and waved for the officer to
come forward.  They took that as suspicious behavior, so they turned on ALL
of their lights--must have been several hundred thousand candlepower.  I
realized that it could only get worse from there, so I turned off the engine
and me and the gal got off to talk to the officers.

I indicated to the officer that I had an unexpected electrical failure.

The officer said that normally when they see someone without headlights,
they may have been drinking.

I pointed out to the officer that on a modern motorcycle, you can't turn off
the headlight, so it wouldn't indicate drinking.  He wasn't pleased that I
had found a flaw in his argument.

They recommended a route home with no traffic and let us go.  However, they
probably felt guilty because they got to watch fatboy (me) push start the
motorcycle AGAIN.  For obvious reasons (warm engine + experience of having
done it once already), it was easier the second time.

I got home.

I got out the electrical diagram from the service manual.  I found that the
headlight current runs through the starter switch so it can be blanked out
to save current during starting.

I disconnected the switch at the harness and shorted to see if I could make
the headlight turn on.  I could.  That indicated that at least one thing was
wrong with the starter switch, so that was most likely the problem.  I
ordered a new one.

It arrived.  I discovered that I had to remove the gas tank to get to the
carb (throttle cables) in order to replace the ignition switch.  It took me
a couple hours.  But the bike then worked fine.

But that raises another question ...

Do you get harmful voltage spikes in a bike running with an open battery?
In a lot of electrical systems, don't they clip some of the alternator
noise?

Thanks, Datesfat

 

wrote:


Yes. If you run the alternator disconnected from the rectifier
regulator (open circuit) it can generate up to 150 volts AC, which can
puncture the enamel insulation of the phase coils, shorting that coil
out and reducing the output voltage.

Normal operation *always* has the alternator stator connected to the
rectifier regulator.


Motorcycle alternators have three phase wye-wound stators with an
ungrounded neutral, so phase A goes to the rectifier regulator and
returns to phase B which goes to the rectifier regulator and returns
to phase C which goes to the rectifier regulator and returns to phase
A.

This means that the phase to phase voltage is 1.73 times the phase to
neutral voltage (which you couldn't measure anyway).

The part of the RR that converts AC to DC is a three phase, full wave
rectifier
with each phase connecting between the anode and cathode of a single
pair of power diodes, so there are a total of six diodes.

If any one diode blows out, the RR output is cut in half.


The typical modern rectifier regulator now has two zener diodes that
sense when the voltage rises above 14.5 volts for bikes with flooded
cell lead acid batteries or 15 volts for sealed AGM batteries.

The zeners trigger silicon control rectifiers that short two phases to
ground for half a cycle.

There is enough internal resistance in the zeners so no large resistor
is needed to shunt the excess current to ground.

As the voltage output from each coil is reduced on the positive half
of the sine wave, the zeners stop triggering the SCR's until the
voltage gets too high on the
negative half of the sine wave.

 

wrote:


Yes. Check the sides of the plastic case to see if it is bulging.
That's a warning sign.


The original equipment fitment for your Shadow was a factory sealed
Yuasa YTZ10S AGM type. They will easily last for 6 to 8 years with no
maintenance, just a trickle charger once a month during the winter
time.

You can tell that a sealed battery is close to the end of its service
life by inspecting the sides of the battery case, which will start to
bulge out or suck in, giving the battery a "starved horse" look.

This occurs because of sulfation, in spite of the absorbed glass mat
holding the electrolyte in close contact with the spongy lead plates.

If your battery gives up the ghost, do not buy a new factory sealed
battery from Honda for around $170 USD.

Check out the walmart.com website and you'll probably get the battery
for around $65~$70.

Filling the dry battery with the special electrolyte that comes in a
bottle in the cardboard box with the battery is very simple.

You fill the battery, trickle charge it for half an hour to an hour,
check to see if the resting voltage half an hour after taking the
battery off the charger is 12.8 volts, then you seal the battery
yourself with the special one-piece cap.

Piece of cake.