Lamps
©
lamps.htm-24A
This article
covers lamp theory, lamp substitutions, updating the /5
headlight, adding relays, fuses, large headlights, heavier gauge
wiring, and HEADLIGHT MODULATORS.
It does not, yet, cover LED lamp substitutions, although I discuss them, SOMEwhat.
Please refer to article(s) on the Airheads Club website; which will have more to say about specific relays, etc. The URL is: http://www.airheads.org Click on that main page for Technical Tips articles.
PLEASE see article 24B, that discusses the headlight relay, the internal diode, the handlebars switch, and how they all work together. It is NOT so simple, and that article information IS needed to understand using larger wattage lamps, relays, ETC.
PART 1:
BMW stock lamps are arguably perhaps the best for
your bike; except for the non-halogen
early /5 headlight lamp & lens/reflector assembly, which is
vastly improved by upgrading the lamp, lens, and reflector, by
the original conversion kit parts or, cheaper perhaps, from an
R65....or using a special
64198 lamp.
It is up to YOU to decide, for one reason or another, to make a
substitution or change or modification. Perhaps you
are on the road and cannot find the correct lamp. Perhaps you
want them brighter or want to add a lamp.
Note that some lamps are direct equivalents, such as the 9003
headlight bulb (for after the early /5, or the
converted /5)...and there are subs available for taillights,
instrument and indicator lamps. Many substitutes will fit in
existing sockets and are quite adequate for use. When
substituting a lamp it is a good idea to THINK about such things
as life expectancy, light output, AND heat
output.
***The early unconverted /5, that is, stock, used a 40/45 watt headlamp, and it was NOT a halogen lamp. It is possible to obtain a H4 in higher power that fits the /5 socket. That is GENERALLY not a great idea with the original lens and reflector, as the light pattern will be so-so, an effect of the glass lens...and the reflector...but SOME folks may like it. Better to use the Kit BMW offered for this; or, the reflector and lens of a R65 will adapt at less cost. The stock 180 watt /5 alternator is adequate. It is possible to update the alternator to the larger size(s) if one has lots of electrical needs, but only a specific size (105 mm stator) fits the /5 engine casting, and that particular stator housing is from some of the 1974-1975 year. However, a high powered alternator to fit all airheads, including the /5, is available, it is called the EnDuraLast....available in 105 mm size for the /5, and 107 mm for later models.
NOTE that the early headlight chrome rings
were not screw/clamp fastened, and many have been lost along the
road, and it is best to fashion a method to secure them at the
very bottom.
NOTE: German or other foreign
auto-parts stores might carry
the 60/55 watt halogen lamp type #64198, an Osram number, which
has a filament arrangement that
will work OK with the stock /5 reflector and lens. see below
The BMW 55/60 watt halogen H4 headlight lamp (similar to common
type 9003 and really same as BP1260-H4) is often changed by owners to much higher
wattage units. Be very cautious about this,
as not only is the airhead alternator output not overly generous,
but the handlebar light switch
is NOT rated for those larger
lamps, and therefore it is a MUST
to use a heavy duty relay (the Bosch 20 or 30 ampere types are
not expensive and are fine for this), using the original light
switch output for the relay coil. You can do this conversion with
ONE relay, if that relay is "SPDT", which means Single
Pole Double Throw. No hard and fast rules here on how to
wire and use the relay(s) and switch gear, installations vary,
depending on what you want to do/have. The second section
of this article has more to say on this matter.
#9003 lamps work fine for stock usage...and there are many
variations, some of which throw better light
patterns. The Eastern Beaver company makes
nifty relay kits, that PLUG IN!
The best lamp I
have found, to be used with stock OR relays, is the Osram lamp 64205, it is
rated at 70/65. It has a very nice output, and at 2000/1350 lumens too.
The blue lamps and other high priced trick lamps may SEEM brighter, but if you are in an oncoming car, you may think differently.....claims of 100 watt output for 55 or 60 watts of power are dead flat wrong and misleading.
****Headlight bulbs run very hot, and the H4 halogen lamps use a type of quartz glass that you must NOT touch with your fingers, which leave often invisible skin oils on the lamp, which shorten the lamp life. If you have handled the lamp glass, clean it with alcohol. This is a good policy for any lamp.
****Headlight reflectors and inside the glass,
will get fogged up by dirt, etc., over a long period of time, and
should be cleaned with alcohol mixed with a drop of detergent and
in some water, and then flushed with clear water. Allow
to dry VERY thoroughly before
installing the lamp, etc. I do not try to separate the
glass part, I do my cleaning through the lamp hole.
Roy Truelsen, once a Member of the Airheads LIST, posted
information to the Airheads Mailing LIST about using larger, more
powerful lamps, particularly for the instruments/pod. His
articles are probably still in the Archives and probably still on
the Club's .org website. Keep in mind that an
incandescent lamp has a very hot piece of metal inside, and that
metal will radiate HEAT. The wattage rating of a lamp is the
power INput to the lamp, and that power is directly proportional
to HEAT. Some lamps are rated only in voltage and current.
Multiply voltage times amperes to get watts. It is possible that
too powerful a lamp will do some heat damage to your lamp socket
area. In fact, that is QUITE possible. I have
theorized that using some such larger lamps that have SO MUCH
extra heat, that they are not only going to melt or deform the
plastics in the area, but may well detract from life of such as
the tach and speedometer/odometer. The later HEADLAMP
sockets are not good with large lamps...early ceramic ones are
fine. I have NOT tested all the possible
combinations of higher wattage lamps for any heat or other
problems in the instruments, nor eyebrow area of the RS/RT.
Part
II
LED's:
NOTE that very bright white LED lamps that fit the indicator sockets on some pod models are now available reasonably priced. However, some give insufficient light output, some are not 12 volt rated, and most do not mount in the original sockets....some that do are now available.
Note also that LED lamps do not always project much light to the sides and also that they do not work in flasher circuits in which the flasher unit is load dependent, without additional changes. BMW has used a number of different flasher circuits on our Airheads...for some, the LED 12 volt lamps, or ones with added resistors work just fine. Many types of LED's and multiple LED lamp assemblies are available commercially. BE cautious about their use, especially for the rear tail light.
Modifying to LED lamps is not necessarily always an improvement. It is pretty easy to remove a pod and replace lamps every few years anyway. You hardly save much in wattage either. It is true that a LED lamp usually lasts almost forever, if properly powered. It may, however, be hard to see, especially in the daytime.
PART
III:
***NOTE that if your bike has one stock rear running lamp, and it
fails, you have NO light to the rear...at all.
Conversion of the turn indicators to have an additional running
lamp function is relatively easy, and an article is posted at
this website:
addingrunninglamps.htm
There are pros and cons to this conversion. The strongest
argument AGAINST the conversion is that the turn signal portion
MIGHT NOT be as visible, when the running lamp is
illuminated. It is actually possible to defeat that, but is
complicated.
When a common lamp fails it is almost always because the filament broke from being thinned, or stretched/sagged, or all these things, over a long period of time. You can generally identify a lamp that is thinking about dying, as the filament is visibly sagging. This is particularly noticeable in the turn signal and taillight lamps. Thus, regularly, you should visually inspect the lamps. This is highly recommended for the rear running and brake light(s). Sudden failure is usually brought about by a characteristic of the wire filament in incandescent lamps. The internal lamp filament wire, a type of tungsten, has a far lower resistance when cold, than when hot. Thus, at the instant the power is applied to the cold lamp filament, the 'inrush' current is very large, and the thinned or otherwise weakened area of the filament fails. As the wire breaks, if the spacing between the broken ends is small enough, and the time that small spacing exists is long enough, the lamp might arc. The lamp MIGHT draw a large current at that time....and in RARE instances, blow a fuse. This effect is FAR more prominent in higher voltage lamps, such as in your house, where the breaking is accompanied often by a bright flash of light due to the arcing. NOTE that when the turn signals are flashing on and off, that type of on-off usage detracts greatly from their official life expectancy.
Note also that book values for lamp life are most often based on AC, not DC, and for NO vibration. At least this is so for American numbers. It is VERY UNclear if all vehicle lamps are rated for DC.
A very special case is a halogen headlight
bulb, where a headlight modulator MIGHT even INcrease its life.
For extremely complex reasons, a halogen headlight bulb may last
LONGER with a modulator, IF the modulator does NOT allow the lamp
to cool too much between 'pulses'. A rate of about 2.5 to 4 per
second, even if fully off and fully on voltage is applied, is
near the optimum for both life AND eye catching
potential! Use of modulators is deemed a strong
SAFETY DEVICE by ME, although others dislike them, feeling that
they annoy oncoming drivers. Use of proper types of
HEADLIGHT modulators are legal in all States, and is codified
into Federal Law for motorcycles.
GENERALLY, a higher voltage-rated
lamp will last MUCH longer, in a circuit that has LESS
than that lamp's rated voltage, at very little cost in light
output. The rule of thumb on LIFE of lamps rated for A.C., is
that the AVERAGE life will be HALF the book value AT BEST.
Life is vastly shorter if a AC rated lamp is used on DC.
BUT...notice!!: life INcreases GENERALLY at the 12th
(some books say 8th) POWER of the INcrease in the voltage rating
of the lamp, above actual circuit voltage. The
DEcrease in life if a lamp has excessive voltage applied to it is
vastly faster, percentage-wise. Thus,
over-voltage applications to lamps means a SHORT
life. The voltage measured AT the rear brake lamp, or
headlamp, or any lamp, is ALWAYS going to be a bit BELOW the
measured BATTERY voltage, and probably a bit below the fairing
voltmeter....by a typical 0.4 volt OR MORE. THUS, a battery
might be floating during cruising at 14.0 volts, the voltmeter
read 13.7, and the brake light when illuminated be actually at
13.2 volts. This has an effect on lamp life,
referring to the RATED voltage of the lamp...which is likely 12.8
for the BRAKE lamp filament.
To restate this a bit clearer, if a lamp is being run at a
slight DEcrease in voltage than it is rated for, the light output
will be almost UNnoticeably lower, but the LIFE will be greatly
extended, and vice versa! NOTE that whilst life of normal
NON-halogen lamps increases, continually, as voltage is dropped,
not so the halogen....which, if temperature drops enough, will
start to lose life....on a complicated curve, which then, as
voltage continues downward, increases life, again. The area
of DEcrease is generally under 11 socket measured volts, so is of
no real effect for our bikes.
DC (direct current...battery power) operation of lamps REDUCES
lamp life. Lamps are generally rated by the manufacturer using AC
(alternating current) power. It is UNclear if headlamps, or even
other vehicle lamps are also rated thusly. Yes, this is peculiar,
because many lamps, not just headlamps, are designed for
vehicles, that hardly have AC systems driving the lamps. There
are some exceptions. My old Vespa had both a DC output for
the battery, coil ignition, and tailight, and an AC output
strictly for the headlight. I have had antique radios
come into my shop that have AC on their dial lamps, and the
lamps are original, and the radio has been in use for 70 years,
at RATED lamp voltage.
Put yet another way: if a lamp is used at its RATED voltage, one
MIGHT, under ideal, non-vibratory, constantly
left on, alternating current operation, obtain its
average rated life. If the voltage is lowered by 10%, or the lamp
is rated at 10% higher voltage than it is being used at, then the
life goes up exponentially. The reverse is true also, BUT the
effect is FAR faster! This means that using a lamp with higher
than rated voltage reduces life VERY quickly. The
measured LIGHT output of a lamp is affected only very slightly,
by a 10% change in voltage. However,
for headlight use, with halogen lamps, it is sometimes worthwhile
to use larger gauge wire, relays, more direct wiring, etc., to
raise the voltage half a volt or more...or to protect expensive
handlebar switches (particularly with larger wattage
lamps). Note that most all modulators DEcrease
headlight voltage very SLIGHTLY, decreasing actual light
SLIGHTLY....and thereby this modulator usage by simply the
SLIGHTLY lower voltage ALSO extends life.
ONE more way to think about this: If your
voltage regulator is set for 14.9 volts (the upper limit for a
Panasonic type of battery), you might expect less life on your
lamps. They will be somewhat brighter
though. Probably 14.3 is a nice value for most
batteries as a compromise. Certainly, the 13.8 that
is often found will extend lamp life considerably.
You can expect your BRAKE and TURN lamps to have REDUCED life
with over 14 volts.
A lamp with 50%-100% greater instrument-measured (or specified)
light output will NOT look all that much brighter to your
eye.
PART
IV:
Lamp equivalents and/or
substitutions:
Various lamps in the
airhead can be substituted WITHOUT problems. Many folks
know that the rear running lamp, BMW 07-11-9-978-227, rated at a
NOMINAL 12 volt and 5 watts, can be substituted by a very
commonly available #97 lamp, which is rated at 13.5 volts at .69
ampere, which means that at THAT voltage, it would draw 9.3
watts. There are substitutes for EVERY lamp. Some are OK, some
perhaps not.
The Alternator lamp is rated at 12 volts
and 3 watts, part number
07-11-9-978-372. The 2825 lamp will offer
more brightness, and a bit more alternator output at the lower
initial rpm area. You can also use the common #168,
etc...see below. There is an article on this website
on adding a resistor in case the lamp fails...which usually stops
the alternator from ANY output. The article is the genlampresistor.htm
article.
Regarding the substitution of #193, #194, #168, #161, #158 used
in the instruments:
These lamps are described officially as style T 3-1/4 and used at
the tachometer, speedometer, turn signal indicator, GEN.
158 lamp = 2.80 watts, .20 ampere, rated 500 hours, a.c. (may be
rated at 13v and .24 ampere), about the same light output as a
193 and 194
161 lamp = 2.66 watts, .19 ampere, rated 4000 hours, a.c.
emergency use only for airheads.
168 lamp = 4.90 watts, .35 ampere, rated 1500 hours, a.c.
This is a particularly good sub for the GEN lamp, as its
characteristics ever so slightly enhance the starting of
charging.
193 lamp = 4.62 watts, .33 ampere, rated 5000 hours, a.c.
(rated at 14 volts too).
194 lamp = 3.78 watts, .27 ampere, rated 1500 hours, a.c.; a bit
less light than 168, 1500 hour life..
2825 lamp = This is a 5 watt Euro spec lamp, commonly also found
in the U.S. .....12 volt rated, not 14 as above lamps; 0.4
ampere, and brighter than 168 and 194, and very nice, if pricey,
replacement for them. NOT super long life. This
lamp develops too much heat, IN MY ESTIMATION, for anything but
the GEN lamp usage.
2821 lamp = 12 volt rated, not 14. 0.25 ampere, light
output fair, only a slight bit more than the 194, and not super
long life, but longer than the bright 2825
ANY of these bulbs will work adequately, the #168 and 2825
being a slightly better choice for the GEN lamp, wherein you want
charging at the lowest rpm point where charging begins. Just a
WEE tad of help though. You WILL more performance by
using the latest 2.8 ohm rotor, if your rotor is an earlier
version. For the GEN lamp, one should
consider doing the resistor modification which will help charging
slightly, and eliminate a charging problem if the lamp burns out
(rare as that is). See the GEN
LAMP Circuit modification on this website.
Be cautious about the 2825 in other areas....due to the heat
developed.
In general an E- prefix means European standards, which may
or may not be better in some instances and is not overly
important.
Instrument lamps #07-11-9-978-279, 12 volt, 2 watt. This is
the hardest lamp to substitute. This lamp has what is
called a PHILLIPS base (BA7S midget Bayonet Base...and a T2
tube...1/4" diameter). The
"BA7s" base is 8.7 mm from top of locating tang to
bottom contact, the barrel diameter is 7.0 mm, tube is 1/4"
diameter, and the width across the located tangs is 8.6 mm.
Equivalents or substitutes for that lamp:
(1) GE 2696; Osram 3898; Philips 12829. These are all
12 volt, 0.167 ampere, 2 watt, and rated at 200 hours.
(2) It is not clear to me that the Eiko SE1274 would
fit. It is 12 volt, 0.125 ampere, 1.5 watt, but the base is
BA7.5..I think...and uses T-1-3/4 shaped
glass.
(3) There is also a Narva 101006 lamp, rated at 12 volts,
.17 ampere, 2.04 watts.
(4) The BA7s base lamps were also used on some old car
radios...and it is possible a repair shop has some 12 volt lamps.
Turn signal and brake lamps: 12 volt, 21 watt
#07-11-9-978-370, substitute is common #1156. The 1156 lamp is
rated 12 volts, 2.1 ampere, 27 watts, 1200 hours (a.c.)....which
is a BIT brighter...you probably won't notice.
For those who have converted their turn signals to be turn and
run lamps, the usually used lamp is a double contact lamp, common
#1157. That lamp has two sections, one is far brighter
(TURN) than the other. The sections are: 12.8 volts, 2.1 ampere,
27 watts, 1200 hours (a.c.); and, 14.0 volts, .59 ampere, 8.26
watts, 5000 hours (a.c.). If your average speed is 40 mph,
1200 hours would give you 48,000 miles on these lamps. I
doubt you will get 10,000, of course. But, that is normal
for any highly stressed turn and brake lamps, stock or not.
The original function lamps, T-1-3/4 style, like
#07-11-9-978-375, were 1.2 watts, very close to the #73 long life
lamp, or the slightly brighter #74 lamp. One could even use a #37
lamp, which is similar to the 73. Another lamp is the E2723,
rated at 2.3 watts. Sometimes these smaller indicator lamps
are hard to find, and an electronics supply company may have them
in stock. You MAY find the E2723 at autoparts stores,
sometimes the others. All these lamps can be used as the
high beam indicator, brake light failure, OIL, and neutral
indicators. LED substitutes are now available, white
output, for these lamps. The power drain is only 0.32
watt, but they are VERY bright...but not all that much of the
brightness is fully usable.
***In a few instances, such as some brake light (stop light)
bulbs, the bulb is rated at 12.8 volts. It is possible for more
than that voltage to be on that bulb in actual use, further
decreasing life, but typically not too much more, as there are
voltage drops in the wiring and connections. What
happens is that the brake lamp drain is high enough such that the
system voltage drops somewhat, much more so by the time you are
stopped, engine is at idle rpm. Still, do NOT expect long
life from turn and brake lamps.
The normally 4 watt parking lamp 07-11-9-978-256 when used in
SOME models in the headlamp REFLECTOR SHELL (on the faired RS/RT
models no lamp was fitted, but CAN BE), can be fitted with
substitutions, and also vastly brighter lamps.
Some might want weak lamps, such as the #1893. There are a
lot of these types of "standard miniature
bayonet" lamps, such as 1889, 1895, 1891, 57 (round lamp on
the 57and 1895). Some folks do this for
'daytime running'. Some folks have a headlight on/off
switch, and use this lamp to save watts, a 5 watt halogen used
here is considerably brighter, and a 10 or 20 watt halogen is
quite bright. Some Airheads are equipped with a headlight switch
(depending on year and model, and Euro or not) that makes
it possible to ride without the headlight on....probably illegal
for some, but this is done anyway. It is possible to
make a small wiring change at the ignition switch and have this
'side of reflector light'...and the ignition....be ON in the PARK
position, and the headlight main bulb on in the normal
position. Don't
use the 10 or larger watt lamps for the RT/RS EYEBROW lamp,
use only for the small socket, described, for the HEADLAMP
reflector. It may be possible to use the 5 or 10 watt
halogen in the eyebrow position, but I see no reason to even try
that, as you would not want to use that for a daytime headlight
function. The eyebrow lamp housing does not like
excessive heat. Some have removed that lamp, and
wired the eyebrow to the place for the socket on the headlight
shell, and used a Phillips Halogen lamp, 10W being 12024; 20 W
being 12452.
FYI: Stock 4 watt: BMW 07-11-9-978-256.
Small radio lamps: The 1893 is similar to the original 4
watt; other numbers usable are 1891, 1895, 1889.
Here is additional information on the higher powered lamps
for the headlight parking lamp position (remember, NOT in the
eyebrow light of the RS/RT!...they are too HOT!):
Parking lamp bulb socket, in case yours is
missing: BMW #62-14-8-680-130; if you want the wiring
harness it is
#61-12-1-358-176
Osram Miniwatt #64111, also known as Sylvania
39431, and Philips 12023, halogen, 5 watt. This lamp may be
OK for use in the eyebrow too.
Osram Miniwatt #64113, Philips 12024, halogen, 10 watt.
Osram Miniwatt ;Sylvania #64115, Philips 12452; Napa-Wagner
47835; Hella 78165; halogen, 20
watt.
NOTE: The 64111, 64113, and 64115 all
are the same size of physical lamp, they use a Euro base style
called a BA9s, and have a 9.3 mm diameter of bulb and MOL
(length) of 33.0 mm. All of these lamps are nominal 12.0
volt rated, and while I do not have life expectancies, I suspect
only a few hundred hours, but may be wrong on that.
Note that these halogen lamps are not overly common, and prices
vary CONSIDERABLY....even 2:1. You can find them by using
Google.com by simply entering something like this for a search
term: 64111 lamp
There are many possible other lamp substitutions possible for
various places on the motorcycle. I have information
available on many lamp numbers.
The actual drain and power/light output of a lamp depends on the
ACTUAL measured voltage at the lamp itself.
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Part IV....more on wiring, lamp life, etc:
Increasing the wire gauge size to the headlight, and/or using a
heavy duty relay and switch, can brighten your headlight by
reducing voltage losses. The stock headlight (except early
/5) is 55/60 watts and the bars switch in particular will
NOT hold up to larger lamps (80 watts probably for awhile, but
not 100+) that one might put in the headlight shell....or for
added headlamps; and, hence a heavy duty 20 or 30 ampere relay
(Bosch types, black, in plastic cases, local autoparts stores,
are relatively INexpensive and OK).
NOTE!...use of a headlight modulator
with an INcreased lamp wattage size also means you should use a
relay.
There are OTHER considerations:
There are some things not usually discussed about changing the
wiring, adding relays, ETC., ....besides the need to do it neatly
and foolproof, so that the bike can not burn up. On THAT
subject, one must avoid poor connections, bare wiring, places
rubbing could compromise the insulation, and, of
course, have a FUSE! IN almost every instance of adding one
or two relays; you will want a direct to battery connection via a
fuse.
BMW could have used larger gauge wires for the
lighting, and elected not to, and had some reasons for what they
did. I hope the following will discuss all the
factors and that I have not forgotten anything:
The light output of a lamp is increased only a
very small amount for a 5% increase in voltage, and that is
probably the improvement you might make at the headlight with a
directly connected larger gauge wire, fuse, switch....or using
heavy wiring and a heavy duty relay. BUT the
LIFE of the lamp is GREATLY decreased,
way out of proportion to the vastly smaller percentage increase
in light. This is a general property of incandescent
lights, including halogen types. Not only is the life
decreased from the lamp life otherwise obtained, but the lamp may
get a slightly higher voltage AT turn-on, and the slightly higher
inrush current on a cold lamp may decrease life a tad more.
Typically, in an airhead, with reasonably decent wiring, switch
contacts, etc., the headlight will see about half a volt less
than the battery, sometimes a bit more. This is a wee bit
less voltage, a couple tenths or so, than the voltage shown on
the fairing voltmeter, if you have one of those and it is
accurate (usually they are accurate). Those
voltmeters usually show 0.3 volt lower than a direct battery
terminal measurement.
Lamps used in vehicles are not all rated at 12
volts. Some are rated at 12.8, or 14.0.
Some foreign, German too, lamps ARE rated at 12 volts nominally,
but the WAY they are rated and tested amounts to about the same
thing as U.S. lamps, in effect, so I will treat them the same,
although they ARE differently rated. Yes, I know that
the Europeans and the U.S., has used slightly different voltages
on some, at times...but the principal here holds up. The
14.0 volt rating is typically used for lamps that are ON all the
time the engine is running. The headlight is a
special case though, and is not thusly rated. The 12.8
rating is generally for lamps that are used only for short
periods, such as turn signals and brake lights. These
lamps usually have a much higher rated wattage than other small
lamps, such as clearance and running lamps and dash lights, and
hence will put more of a load on the system, and typically the
engine is idling, or producing little electricity from the
alternator, and the manufacturer's KNOW that the voltage AT THE
LAMPS will thus be reasonably close to that 12.8, and hence that
is the rated voltage. A case could be made by nerdy
engineer-types about the faster lighting-up, or the transient
period from high system voltage to the decreased voltage...but I
won't get into that here. The headlamp is a special
case, and has complicated ratings, not easily found in
specification books.
When you raise the system voltage, whether by
an alternator conversion that increases the voltage at idle or a
bit above, and/or, by higher voltage regulator settings, larger
gauge wires, relays, etc.....you can expect shorter lamp
life. That is the tradeoff. There is another, more
minor tradeoff, in that the DRAIN in watts will also be a bit
higher. You may find that all the special
wiring and relays, for the stock lamp, don't make a lot of
difference. You can find
out how much difference it MIGHT make, if things you contemplate
doing were near perfect, by turning on the headlight, and then
ADDING, temporarily, a heavy duty wire from the battery +
terminal directly to the energized headlight terminal. Do
this at idle rpm, and do it with the system at an rpm (and
battery fully charged) that has the maximum system voltage.
If your bike has larger voltage drops, you
probably need to attend to the various connections, plugs,
sockets, even relays and ignition switch, etc. One
of the worst places for problems is the larger gauge red wire
connections at the starter relay, and at a slightly loose starter
motor solenoid terminal. Other places often having problems
are the connections at the diode board.
Those who are running heated clothing during
the daytime, and are running at or near the limits of alternator
output, and do not wish to spend the $$$ for the alternator
conversion, can consider a headlight modulator, which will save
quite a few watts (in effect)....besides adding to your safety
(and annoying oncoming drivers, SOME will undoubtedly
say). Those with an additional headlight and heated
clothing MUST have larger alternators.
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Part
V:
HEADLIGHT MODULATORS, in depth, and recommendations:
I am a big fan of Headlight Modulators. I always have
mine ON during the daytime, which means I have a blinking Hi
Beam, since that is what I leave on. Others hate
them, feel they annoy folks. Frankly, the purpose is not to
annoy, but to attract attention, and they seem to do that fairly
well, although in really bright sunlight your headlight is
perhaps not easy to see from an oncoming car driver's standpoint.
But, that is true for any headlight, modulator or not. I
think they are just one extra safety item. One
of my nicknames, from a Club I ride with now and then, is
BLINKY...due to my modulators. I have (HAD, it is sold) a
custom high power modulator on my sidecar tug (1983 R100RT), had
it for maybe 19 years. It was massive, will power an
aircraft landing light (don't ask!).
Prior to that bike, there was a home-made modulator on my
R75/5. I presently have a Kisan unit on my solo bike (1984
R100RT), and put a Kisan modulator into Lilli's R80ST as a little
gift, and have a Kisan modulator on my K1100LT-EML sidecar
rig. The Kisan unit is available from quite a few
motorcycle dealers, and they are not cheap, retail is around
$100.00, but they are really trick, neat units. I've
installed dozens of them. They are programmable, neat-O,
and reliable. Mount the photocell unit cleverly. Ask
me, if you have questions on that.
Decades ago, modulators were of all sorts of types and
usages. NOWadays, the frequency, duration, etc., of the
headlight period on versus off is specified in Federal Law.
Also specified is the use on only the high beam.
Oversimplified here, but close enough. Because of the
Federal law, and Federal money into the States' road systems,
headlight modulators for motorcycles are approved in every
State. Some States have their own laws, but I don't know of
any that negate the federal requirements, I suppose that is
possible on non-federal roads, but have heard nothing like
that. So, for practical matters, they are legal
everyplace. If you want to make your own modulator,
some schematics are on the www.ibmwr.org
website. One version will modulate either beam, as it is
inserted into the stock headlamp ground circuit.
A CLEVER headlight modulator comes from
the company called KISAN (KisanTech).
These are simple to install, since they are a wafer affair that
simply plugs into the rear of the headlamp bulb, then you plug in
the regular cable. There is NO wiring to connect to power or
ground, etc. The Kisan unit has another cable, that
is thin and long enough, it plugs into the wafer unit on some
models, and the other end of the cable is the photocell, a
requirement. The unit automatically works on only the
high beam because of how it's plug is made; and, will not operate
at night due to the photocell. The photocell has three
sensitivities and you program the unit, if you have to, usually
not, by simply turning the key rapidly on and off per the booklet
that comes with every unit. It is very easy to
install, usually without drilling any holes anyplace, or just one
small one. I like the design, obviously, since I have
installed dozens. I recommend another type, from EasternBeaver.com,
below.
Because there are several types of
headlight bulbs used on motorcycles, one has to get the proper
Kisan model. They handle up to a 100 watt lamp.
In operation, you still have the various stock functions of your
left bar switches. Due to a peculiarity of the halogen H4
headlight bulb, your headlight, on the high beam at least, will
probably last LONGER, generally, than without the
modulator. NOTE!....Light output
is improved with a headlight modulator by using a heavy duty
relay. You don't HAVE TO do that, however, as the
light output increase is rather small or modest. HOWEVER,
if you are using a high wattage lamp (over 60 watts), then it is
a must. You can do this with one or two Bosch relays
yourself, or just buy EasternBeaver's modulator with
relays. Frankly, I have NOT found it necessary to use
headlight relays UNLESS the lamp is OVER the stock 55/60
watt....then relays are mandatory anyway to protect the switch on
the bars.
Somewhat technical:......a modulator can
be made in two standards ways. In one method, the
modulator is turned on, then fully off, at a roughly 4 Hertz
rate. In another method, the Federals specify this, the
modulator does not fully turn off during the flashing mode. The
flashing mode is set at 4 Hz to annoy (become more recognized...)
the brain alpha rhythms...or some such. On a
practical basis it makes NO difference about turn-on, turn-off,
as the rate of flashing is fast enough, and equal enough in time
between on and less on or off periods, that the bulb filament
never 100% cools off. The law was wishy-washy on how it was
worded...does headlight power mean electric or light
output? ONE OTHER good thing comes from
the use of a modulator. Since the period of time the
modulator is ON is not constant, the EFFECTIVE use of WATTS from
your charging system is REDUCED. I have not made a
quantitative study of this, but you should gain 20 to 30 watts
effectively. There is also a very SMALL voltage drop in the
unit, but it has only a FAINT effect on light output and
drain. I
am sure to get hate mail over this, but I happen to like things
that add to safety, and I THINK these things DO. And the
lamps last longer, and you get some additional watts from the
alternator on high beam daytime use.
NOTE that Jim at http://www.Easternbeaver.com
has a lot of interesting goodies, including
relays for when you use higher powered lamps or just want more
solid voltage to your headlight. LOTS of good wiring things
on this site, and Jim is a good guy to boot. He has a very
clever combination modulator and relays setup, almost plug and
play, that does it all for you.
Resources:
The above URL's has a lot of lamp information,
but I do not agree with some minor portions of them;..for
instance the inference that DC and AC life is not all that
different....other places here....but GOOD stuff otherwise.
http://lighting.mbz.org/tech/tech.html
This is the URL for extensive information on
lighting, which will dispel a lot of wrong information on
lamps...it is a very extensive data and information base,
covering MUCH that is not here on the page you are
reading. Plan on spending some time browsing.
Revisions:
to 02/03/2003: clarifications:
headlamp shell, use of 9003 in /5; minor additions to
descriptions; headlamp and eyebrow lamps usage and add socket and
harness numbers.
04/17/2003: add .htm title; clarifications here and there.
07/13/2003: /5 large alternator information clarified; add
2825, 2821, and some notes on these types; resources URL's.
09/15/2003: lots of clarifications and includes LED
indicators information, more links.
11/22/2003: Clarify 20 watt lamp and part numbers
01/03/2004: revise in several places for clarity, add
section on wire gauges, relays, and in-depth lamp life
considerations. Add -24 ID to top of article
04/03/2004 : Greatly expand section on side headlight shell
information; also add #64198 for /5; edit entire article a bit.
08/25/2004: minor updates, comments on 2825
10/29/2004: add part 3.
07/05/2005: lamp information updated for 64115
03/23/2006: slight updating
03/25/2006: more lamp substitutions for BMW -279.
03/26/2006: final extensive editing
02/07/2007: minor editing, mostly for clarity
01/08/2008: fix URL's; add Eastern Beaver information; and
revise the modulator section
06/26/2008: add Osram 64205 information