6 or 12 volt battery system - normal voltage range when revving up?

[1970 Suzuki TS250]

I have a 1970 Suzuki TS250 motorcycle. It has a 6 volt system.

A guy ran my bike with a dead battery (it was dry, with no
electrolyte) and this seems to have lead to burnt out headlight. I
wonder if anything else should be checked.

I added a new well charged battery, and when running at idle (with no
lights on (I removed and still have replaced the headlight) I get
about 7.3 volts. But when I rev up the engine to about 6000 rpm I'll
get up to 9-9.3 volts. This seems high to me, but I would like to
confirm with others.

Questions:
1. WHat is the voltage range on your 6 (or 12) volt system motorcycle
at idle, engine revving (rpm?) without headlight and revving WITH
headlight (lo) then (hi beam)? I assume 12V system divided by 2 will
give normal ranges for the 6V system.

2. What is a normal range?

3. Should I run other electrical tests with the volt / ohm / ahm
meter? to make sure I don't blow the next headlight? rectifier? I am
not sure if this magneto equipped bike has a voltage regulator.

The search begins for a 6 volt headlight replacement - the original
Suzuki part has been discontinued.

Thanks!

[Michael Sierchio]

Post by 1970 Suzuki TS250
1. WHat is the voltage range on your 6 (or 12) volt system motorcycle
at idle, engine revving (rpm?) without headlight and revving WITH
headlight (lo) then (hi beam)? I assume 12V system divided by 2 will
give normal ranges for the 6V system.

A "12V" battery at rest should supply 2.2V x 6 = 13.2V. Typical
voltage when alternator is running is ~ 14.4V. A 6 Volt battery
has either three cells, or three pairs of bridged cells. I can't
comment meaningfully on 6V charging systems.

[The Older Gentleman]

Post by 1970 Suzuki TS250
1. WHat is the voltage range on your 6 (or 12) volt system motorcycle
at idle, engine revving (rpm?) without headlight and revving WITH
headlight (lo) then (hi beam)? I assume 12V system divided by 2 will
give normal ranges for the 6V system.

I find it's generally a bit lower, especially on old bikes where the
years have taken their toll of the connections and they're a bit
corroded, increasing the resistance.

Generally, 6.2-6.5v.

[Tom Kimberly]

What size is the head light? 5 1/2" dia? Does it have a bracket on it for
adjusting? If so, take a look at one for a Yamaha DT1.

Tom

Post by 1970 Suzuki TS250
I have a 1970 Suzuki TS250 motorcycle. It has a 6 volt system.
A guy ran my bike with a dead battery (it was dry, with no
electrolyte) and this seems to have lead to burnt out headlight. I
wonder if anything else should be checked.
I added a new well charged battery, and when running at idle (with no
lights on (I removed and still have replaced the headlight) I get
about 7.3 volts. But when I rev up the engine to about 6000 rpm I'll
get up to 9-9.3 volts. This seems high to me, but I would like to
confirm with others.
1. WHat is the voltage range on your 6 (or 12) volt system motorcycle
at idle, engine revving (rpm?) without headlight and revving WITH
headlight (lo) then (hi beam)? I assume 12V system divided by 2 will
give normal ranges for the 6V system.
2. What is a normal range?
3. Should I run other electrical tests with the volt / ohm / ahm
meter? to make sure I don't blow the next headlight? rectifier? I am
not sure if this magneto equipped bike has a voltage regulator.
The search begins for a 6 volt headlight replacement - the original
Suzuki part has been discontinued.
Thanks!

...

[krusty kritter]

A guy ran my bike with a dead battery (it was dry, with no electrolyte) and

this seems to have lead to burnt out headlight. I wonder if anything else
should be checked.

Two-stroke enduro type motorcycles of the 1970's often
used a "balanced" charging system, where the lighting system and the battery
consumed just enough electrical load that the motorcycle didn't need a voltage
regulator...

There was often a headlight switch position that connected extra lighting coils
to the system when the headlight switch was ON and disconnected the extra
lighting coils when the switch was OFF...

Running the engine with the headlight switch ON and a bad battery will blow out
all the light bulbs...

That's what happened to my 1968 Yamaha 250 DT-1. Even though another rider
warned me if the headlight bulb blew out with no battery installed, all the
other bulbs would burn out too. But, I just had to try it and prove to myself
that he was wrong...

He wasn't wrong, but Japanese electrical parts like light bulbs weren't that
expensive in 1968...

But when I rev up the engine to about 6000 rpm I'll get up to 9-9.3 volts.

This seems high to me, but I would like to confirm with others.

Check your owner's manual wiring diagram or the diagram in a Clymer or
Chilton's manual...

I'll bet you a cyber beer that you can't find a voltage regulator on the
diagram...



# * 0 * #
^

[mike]

Post by krusty kritter

A guy ran my bike with a dead battery (it was dry, with no electrolyte) and

this seems to have lead to burnt out headlight. I wonder if anything else
should be checked.
Two-stroke enduro type motorcycles of the 1970's often
used a "balanced" charging system, where the lighting system and the battery
consumed just enough electrical load that the motorcycle didn't need a voltage
regulator...
There was often a headlight switch position that connected extra lighting coils
to the system when the headlight switch was ON and disconnected the extra
lighting coils when the switch was OFF...
Running the engine with the headlight switch ON and a bad battery will blow out
all the light bulbs...
That's what happened to my 1968 Yamaha 250 DT-1. Even though another rider
warned me if the headlight bulb blew out with no battery installed, all the
other bulbs would burn out too. But, I just had to try it and prove to myself
that he was wrong...
He wasn't wrong, but Japanese electrical parts like light bulbs weren't that
expensive in 1968...

But when I rev up the engine to about 6000 rpm I'll get up to 9-9.3 volts.

This seems high to me, but I would like to confirm with others.
Check your owner's manual wiring diagram or the diagram in a Clymer or
Chilton's manual...
I'll bet you a cyber beer that you can't find a voltage regulator on the
diagram...
# * 0 * #
^

...

These bikes rely on the battery to take up all the slack in the system.
A NEW, New, New battery will do that. After a few months, the voltage
starts to creep up. A light blows out causing further stress on the
others. "snowball" comes to mind.
Make sure you get the right lights. Lamps with lower drain will
overstress themselves and others.
I got tired of spending $35 for a new headlight and another $25 for
a battery every year on my '75 CB125S. I put a homemade shunt regulator
on it and have had no problems since. Think of it as a power zener diode.

mike
--
Return address is VALID.
Bunch of stuff For Sale and Wanted at the link below.
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Compaq Aero floppy,ram,battery.
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Toshiba & Compaq LiIon Batteries, Test Equipment
30pS pulser, Tektronix Concept Books, spot welding head...
http://www.geocities.com/SiliconValley/Monitor/4710/

[1970 Suzuki TS250]

Thanks for the replies so far folks - it is quite helppful. Other
comments suggestions are still welcome.

1. The older gentleman reported 6.2-6.5 volts. Has anybody else
measured the voltage at the battery terminals with a voltmeter at idle
and higher rpms?

2. Tom suggested that the headlight might be similar to a Yamaha DT1,
reporting that the headlight diameter on those were 5.5inches. On the
1970-1979 Suzuki TS250 the sealed beam (discontinued) is 6V/25W/25W
(at some point they went to 30W/30W), and unfortunately it is 6 and
1/8 inch external diameter (with a horseshoe shape, ie flat bottom
that was a Suzuki signature apparently). So the 5 1/2 may be a bit
small. to fit in the bucket using the ring that holds it. Ideally a 6
inch could be found, but 5 and 3/4 seems more common, or some
aftermarket type assembly.

3. Krusty Kritter gives a great review of the problem with early 70s
charging system - I am getting acquainted with that. I'll try to get
my hands on a TS250 1970 shop manual (the owner's manual does not
specify anything about a regulator, and I sure haven't seen one yet!
A cyber beer for you looks likely! The rectifier seems to do its job
of converting the AC to DC, with infinite in one direction and very
little resitance (about 50ohms) in the other direction.

4. mike suggested that I'll be at risk as soon as the battery gets a
little older... Glad to read about this - I would like to know which
specific part you used to build your regulator, if you care to teach
me - I could order them online from some electronics store (suggestion
welcome) but I would need a shopping list and description to build
this. Perhaps someone has put it on the web?. I think this is what
the BAT-PAC http://battery-eliminator.com/ is, it retails for about
50$+shipping. Mike also wrote "Make sure you get the right lights.
Lamps with lower drain will overstress themselves and others." If the
original lamp was 6V25W25W, does this mean that I can use a 6V30W30W
safely but not a 6V20W20W safely? Do you happen to know if one or
both filaments light up when the high beam is on (2 filaments would be
50W draw right?).

SO it looks like the best option will be to build my own 6V regulator
and replace the battery with that (or do you leave the old battery in
the system Mike?). I am not sure exactly what a "zener diode" is.

Cheers!

TS250 Suzuki 1970

[Rick Cortese]

Post by 1970 Suzuki TS250
Thanks for the replies so far folks - it is quite helppful. Other
comments suggestions are still welcome.
1. The older gentleman reported 6.2-6.5 volts. Has anybody else
measured the voltage at the battery terminals with a voltmeter at idle
and higher rpms?

From the manual for a 1974 Honda MT250
Light off
RPM 1000 5000 8000
6.3V 8.0V 8.9V
amps --- 1.5 4.1 measured from the positive battery lead to + battery
terminal.

Post by 1970 Suzuki TS250
2. Tom suggested that the headlight might be similar to a Yamaha DT1,
reporting that the headlight diameter on those were 5.5inches. On the
1970-1979 Suzuki TS250 the sealed beam (discontinued) is 6V/25W/25W
(at some point they went to 30W/30W), and unfortunately it is 6 and
1/8 inch external diameter (with a horseshoe shape, ie flat bottom
that was a Suzuki signature apparently). So the 5 1/2 may be a bit
small. to fit in the bucket using the ring that holds it. Ideally a 6
inch could be found, but 5 and 3/4 seems more common, or some
aftermarket type assembly.

...

I've read posts by people that say running a 55 Watt 12V headlight works
on a 6V system, output is about the same as a 25 Watt 6V and current
drain is the same. Ohms Law thing.

Post by 1970 Suzuki TS250
3. Krusty Kritter gives a great review of the problem with early 70s
charging system - I am getting acquainted with that. I'll try to get
my hands on a TS250 1970 shop manual (the owner's manual does not
specify anything about a regulator, and I sure haven't seen one yet!
A cyber beer for you looks likely! The rectifier seems to do its job
of converting the AC to DC, with infinite in one direction and very
little resitance (about 50ohms) in the other direction.

It may just have a rectifier. Honda just dumped the excess
voltage/current into a power resistor. I have a 71 TC 250 that was
stripped down so I don't know if it used the same scheme. IIRC some of
the bikes back then even ran AC from the alternator straight into the
lighting system.

[krusty kritter]

I think this is what the BAT-PAC http://battery-eliminator.com/ is, it

retails for about 50$+shipping.

A "battery eliminator" is just a big condensor that stores enough electricity
from your alternator to keep a battery-and-coil ignition system running at very
low engine speed, like while kick starting the bike, or while idling the
engine...

I'm not sure whether your TS-250 is a 2-cylinder X-6 Hustler, or if it's a
single cylinder enduro type...

The twin cylinder bikes would have had a battery-and-coil ignition system,
while the single-cylinder enduro types would have had an external flywheel
magneto with a low voltage ignition coil that produced just enough power to
send up a single wire to the ignition coil. That is called an
"energy transfer magneto". A battery eliminator won't help the ignition system
on a bike like that...

Old British bikes had energy transfer magnetos...

SO it looks like the best option will be to build my own 6V regulator and

replace the battery with that (or do you leave the old battery in the system
Mike?)

There was a line in an old 1960's rock 'n' roll song that went, "Easier, easier
said than done!"

An impecunious friend got tired of buying voltage regulators and alternator
stator windings for his Suzuki and I gave him a circuit diagram with values for
various components. He felt like he was "beating the system" by building his
own shunt type regulator, but he kept blowing up alternator stators...

He had a small battery charger built into his bike under the seat and kept the
bike plugged into a wall socket in the car port. He couldn't go too far from
home at night...

And, yes, if you install a shunt type voltage regulator on your motorcycle, it
does need a good condition battery to provide voltage stability and absorb
current surges. No battery in the system will cause wiring and stator windings
and diodes to burn up...

I am not sure exactly what a "zener diode" is.

The first zener diodes we saw on motorcycles were also on old British bikes,
underneath the headlight, in a large diameter, finned heat sink. The zener case
was maybe an inch or more in diameter...

A zener diode doesn't conduct much current until it reaches "avalanche"
voltage. Then it starts conducting a lot of current. The zener diodes were
attached to the generator output wire. When the voltage reached a desired
avalance level, the zener diode would simply ground out the generator, dropping
the voltage down below avalance level, and the zener would stop conducting.
Then the voltage would build up again and the voltage regulation was
accomplished by simply grounding the generator over and over and over. The
unwanted excess current would be radiated as heat to the air passing under the
headlight...

That's not so very much different from the way a shunt-type voltage regulator
works. A solid state device called a silicon controlled rectifier (think of it
as a very
robust power transistor) gets a gate signal from a much smaller zener diode
than was used on the old Brit bikes.
The silicon control rectifier then grounds out one leg of the 3-phase
alternator, cutting output current in half. The little zener diodes inside
shunt regulators are probably 1/8th of an inch long...

If the original lamp was 6V25W25W, does this mean that I can use a 6V30W30W

safely but not a 6V20W20W safely?

That's only about 20% more power than the stock headlamp used, you shouldn't
have any problem with that bulb...

I replaced the original equipment 30/30 quartz bulbs in my FZR-1000 with 55/60
quartz bulbs (almost twice as much lighting power) and haven't burned up any
wiring.

Some night ride-loving sportenthusiasts have replaced 30/30 bulbs with 80/100
(very illegal off-road bulbs) and with that much power, it's possible to *melt*
a plastic headlight housing...

Do you happen to know if one or both filaments light up when the high beam is

on (2 filaments would be
50W draw right?).

Nope. The headlight switch selects one filament or the other, not both. But a
guy I used to ride with (he enjoyed going off on 1000 mile rides to be
completed in 24 hours)
would wiggle and fiddle with the knob on his dimmer switch to find a point
where both bulbs were on at the same time...

Problem with doing that, is what do you do if one filament blows out and takes
the other filament out, too?

While you're riding 80 mph around a curve on a dark mountain road?



# * 0 * #
^

[1970 Suzuki TS250]

Thanks for your further replies... I add some thoughts and more
questions for the electrically enclined here, including one question
for Mike and one for Rick (if they can elaborate on their previous
post as per the questions below, unless someone else can answer.

Post by krusty kritter
A "battery eliminator" is just a big condensor that stores enough electricity
from your alternator to keep a battery-and-coil ignition system running at very low engine speed, like while kick starting the bike, or while idling the
engine...
I'm not sure whether your TS-250 is a 2-cylinder X-6 Hustler, or if it's a
single cylinder enduro type...

1970TS250 is an ENDURO-type single cylinder with a magneto flywheel.

Post by krusty kritter
The twin cylinder bikes would have had a battery-and-coil ignition system,
while the single-cylinder enduro types would have had an external flywheel
magneto with a low voltage ignition coil that produced just enough power to
send up a single wire to the ignition coil. That is called an
"energy transfer magneto". A battery eliminator won't help the ignition system
on a bike like that...

OK - noted. But the aim is not to help the ignition system, but to
regulate the voltage in the night mode to prevent blowing bulbs. I
found the specs for the 1970 TS250 in an original owner's manual that
I ordered:

Charging current at 2000 rpm in day mode (the circuit for the bulbs is
open (off) in day mode, with battery charged and neutral indicator
lamp (3Watts) turned on: 0.2A

Charging current at 8000 rpm in day mode (the circuit for the bulbs is
open (off) in day mode, with battery charged and neutral indicator
lamp (3Watts) turned on: below 3.2 A

Charging current in Night mode: no info shown just "--"

Lighting VOLTAGE (use a fully charged battery) day mode (no info
shown, just "--")

Lighting VOLTAGE at 2000 rpm in night mode (the circuit for the bulbs
is closed(on) in night mode, with headlamp (25 watts), tail lamp,
speedometer lamp, tachometer lamp, neutral lamp turned on (3W): over
6.0 Volts

Lighting VOLTAGE at 8000 rpm in night mode (the circuit for the bulbs
is closed(on) in night mode, with headlamp (25 watts), tail lamp,
speedometer lamp, tachometer lamp, neutral lamp turned on (3W): BELOW
8.5 Volts

The above are specs from the book - I am waiting for my bulbs to
arrive before I test the motorcycle. THe wiring diagram shows both an
AC voltmeter around the bulbs and a DC voltmeter around the battery.
Should I test either the DC or the AC (I am not sure if my ammeter /
voltmeter will do AC volts) and this will yield the same values, or
should those be different values? I noted that Rick reported:

"From the manual for a 1974 Honda MT250
Light off
RPM 1000 5000 8000
6.3V 8.0V 8.9V
amps --- 1.5 4.1 measured from the positive battery lead to +
battery
terminal."

But I wonder how the voltage is measured (in parallel, DC on battery
terminals or in parallel AC on headlight wires?

Post by krusty kritter
And, yes, if you install a shunt type voltage regulator on your motorcycle, it does need a good condition battery to provide voltage stability and absorb
current surges. No battery in the system will cause wiring and stator windings and diodes to burn up...

But Mike had written:
"These bikes rely on the battery to take up all the slack in the
system.
A NEW, New, New battery will do that. After a few months, the voltage
starts to creep up. A light blows out causing further stress on the
others. "snowball" comes to mind.
Make sure you get the right lights. Lamps with lower drain will
overstress themselves and others.
I got tired of spending $35 for a new headlight and another $25 for
a battery every year on my '75 CB125S. I put a homemade shunt
regulator
on it and have had no problems since. Think of it as a power zener
diode."

I wonder if Mike can comment if he uses a new battery or what he keeps
instead?

And if I don't make a shunt regulator, can I buy one and put it in the
system? Where?

TS250

[Rick Cortese]

Post by 1970 Suzuki TS250
"From the manual for a 1974 Honda MT250
Light off
RPM 1000 5000 8000
6.3V 8.0V 8.9V
amps --- 1.5 4.1 measured from the positive battery lead to +
battery
terminal."

Voltage is measured in parallel with the battery. Current is in series
with the VOM between the positive lead/wire to the battery terminal and
the battery post. That is, you disconnect the postive terminal and the
VOM is in between to complete the circut.

Post by 1970 Suzuki TS250
But I wonder how the voltage is measured (in parallel, DC on battery
terminals or in parallel AC on headlight wires?

OK, I don't have a TS 250 but I do have an RM125, TM400, and two TS 185
engines to look at. I'm assuming the 185s are most like yours. They have
4 coils comprised of two for the CDI voltage and trigger and two for
lighting/battery. I don't have lights on the 185 or a manual but I
assume they use a similar scheme to Honda with the lighting being able
to be powered by AC or the battery when the engine is off.

There is an online schematic of a Honda at
http://www.honda-elsinore.com/

The *ONLY* one I could find there that is actually online and pertains
to a street bike with lighting will be the one for the MT125.

Ignore the coil/point parts and the other stuff may be close.

[mike]

Post by 1970 Suzuki TS250
Thanks for your further replies... I add some thoughts and more
questions for the electrically enclined here, including one question
for Mike and one for Rick (if they can elaborate on their previous
post as per the questions below, unless someone else can answer.

Post by krusty kritter
A "battery eliminator" is just a big condensor that stores enough electricity
from your alternator to keep a battery-and-coil ignition system running at very low engine speed, like while kick starting the bike, or while idling the
engine...
I'm not sure whether your TS-250 is a 2-cylinder X-6 Hustler, or if it's a
single cylinder enduro type...

1970TS250 is an ENDURO-type single cylinder with a magneto flywheel.

Post by krusty kritter
The twin cylinder bikes would have had a battery-and-coil ignition system,
while the single-cylinder enduro types would have had an external flywheel
magneto with a low voltage ignition coil that produced just enough power to
send up a single wire to the ignition coil. That is called an
"energy transfer magneto". A battery eliminator won't help the ignition system
on a bike like that...

OK - noted. But the aim is not to help the ignition system, but to
regulate the voltage in the night mode to prevent blowing bulbs. I
found the specs for the 1970 TS250 in an original owner's manual that
Charging current at 2000 rpm in day mode (the circuit for the bulbs is
open (off) in day mode, with battery charged and neutral indicator
lamp (3Watts) turned on: 0.2A
Charging current at 8000 rpm in day mode (the circuit for the bulbs is
open (off) in day mode, with battery charged and neutral indicator
lamp (3Watts) turned on: below 3.2 A
Charging current in Night mode: no info shown just "--"
Lighting VOLTAGE (use a fully charged battery) day mode (no info
shown, just "--")
Lighting VOLTAGE at 2000 rpm in night mode (the circuit for the bulbs
is closed(on) in night mode, with headlamp (25 watts), tail lamp,
speedometer lamp, tachometer lamp, neutral lamp turned on (3W): over
6.0 Volts
Lighting VOLTAGE at 8000 rpm in night mode (the circuit for the bulbs
is closed(on) in night mode, with headlamp (25 watts), tail lamp,
speedometer lamp, tachometer lamp, neutral lamp turned on (3W): BELOW
8.5 Volts
The above are specs from the book - I am waiting for my bulbs to
arrive before I test the motorcycle. THe wiring diagram shows both an
AC voltmeter around the bulbs and a DC voltmeter around the battery.
Should I test either the DC or the AC (I am not sure if my ammeter /
voltmeter will do AC volts) and this will yield the same values, or
"From the manual for a 1974 Honda MT250
Light off
RPM 1000 5000 8000
6.3V 8.0V 8.9V
amps --- 1.5 4.1 measured from the positive battery lead to +
battery
terminal."
But I wonder how the voltage is measured (in parallel, DC on battery
terminals or in parallel AC on headlight wires?

Post by krusty kritter
And, yes, if you install a shunt type voltage regulator on your motorcycle, it does need a good condition battery to provide voltage stability and absorb
current surges. No battery in the system will cause wiring and stator windings and diodes to burn up...

"These bikes rely on the battery to take up all the slack in the
system.
A NEW, New, New battery will do that. After a few months, the voltage
starts to creep up. A light blows out causing further stress on the
others. "snowball" comes to mind.
Make sure you get the right lights. Lamps with lower drain will
overstress themselves and others.
I got tired of spending $35 for a new headlight and another $25 for
a battery every year on my '75 CB125S. I put a homemade shunt
regulator
on it and have had no problems since. Think of it as a power zener
diode."
I wonder if Mike can comment if he uses a new battery or what he keeps
instead?

...

Nope, I use an OLD battery. That's the whole idea.
Shunt regulator is just a BIG transistor on a heat sink with a smaller
zener diode in the base. Since there's no way to turn it off, I had to
put it after the ignition switch. I stuck it under the seat and tapped
into the tail light wire. Since there's significant voltage drop in
those old 6V systems, I just picked a zener that kept the voltage at
the headlight within limits. The battery doesn't ever get fully
charged, but I don't drive it at night, so I don't care. Just gotta
have a light on in the daytime to comply with local laws. Headlight
gets real dim when I step on the brake...but it don't burn out...

There are issues. You could conjure up a situation where you put in a
new fully charged battery and closed the ignition switch. LOTS of
current could go thru the zener. In a practical situation, if you
don't externally charge the battery, this shouldn't happen.

If I were to do it again, I'd use a PIC processor and do the whole
thing digitally.

Best thing I can think of is to sell any 6V motorcycle to a collector
and get on with more current technology...yeah right...
mike

Post by 1970 Suzuki TS250
And if I don't make a shunt regulator, can I buy one and put it in the
system? Where?
TS250

--
Return address is VALID.
Wanted, 12.1" LCD for Gateway Solo 5300. Samsung LT121SU-121
Bunch of stuff For Sale and Wanted at the link below.
HP200LX 10MB + MODEM + LEATHER CASE
Sony Digital Camera
Compaq Aero floppy,ram,battery.
FT-212RH 2-meter 45W transceiver.
Toshiba & Compaq LiIon Batteries, Test Equipment
30pS pulser, Tektronix Concept Books, spot welding head...
http://www.geocities.com/SiliconValley/Monitor/4710/

[Rob Kleinschmidt]

Post by 1970 Suzuki TS250
I have a 1970 Suzuki TS250 motorcycle. It has a 6 volt system.
A guy ran my bike with a dead battery (it was dry, with no
electrolyte) and this seems to have lead to burnt out headlight. I
wonder if anything else should be checked.
I added a new well charged battery, and when running at idle (with no
lights on (I removed and still have replaced the headlight) I get
about 7.3 volts. But when I rev up the engine to about 6000 rpm I'll
get up to 9-9.3 volts. This seems high to me, but I would like to
confirm with others.
1. WHat is the voltage range on your 6 (or 12) volt system motorcycle
at idle, engine revving (rpm?) without headlight and revving WITH
headlight (lo) then (hi beam)? I assume 12V system divided by 2 will
give normal ranges for the 6V system.
2. What is a normal range?
3. Should I run other electrical tests with the volt / ohm / ahm
meter? to make sure I don't blow the next headlight? rectifier? I am
not sure if this magneto equipped bike has a voltage regulator.
The search begins for a 6 volt headlight replacement - the original
Suzuki part has been discontinued.

...

I would guess normal battery range ought to be about 6.3 - 7 volts max
with the engine running. Above that and you're pretty likely to be
boiling the battery dry.