INSTALLING AN ACCESSORY ELECTRICAL OUTLET
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accessoryoutlet.htm-27
There is nothing very
complicated about installing the standard accessory
outlet (socket)(jack) onto almost any airhead. The female
socket and male plugs are available from John Deere
dealerships, not just BMW. There are many other sources
...and various styles of these sockets are
available. Deere prices are now up, and
it is likely best to get them from your BMW motorcycle
dealership. HOWEVER, Radio Shack has
stocked one or two cheap adapter cables that could easily have
the plug removed. Some folks will purchase enough of the male
plugs to allow battery chargers, heated clothing, maybe ice cream
makers (seen that). The
BMW plug and jack are of higher quality than most any other type,
and I recommend the BMW ones from your BMW dealership....or, from
a quality supplier. Sources for electrical accessories are listed
in my references article.
An accessory jack should incorporate
a FUSE in the POSITIVE (+) lead (the
lead that goes to the CENTER jack contact, the STOCK size was 8
amperes), and be wired directly to the battery, unless you have a
REALLY GOOD reason to wire it through the ignition switch. I
suggest wiring directly via a fuse to the battery, thereby
avoiding having to have the ignition switch on...and....the
accessory socket (jack) is a great place to plug in your battery
charger, and thereby avoid problems with alligator clips, sparks,
etc. You wouldn't want the key ON, during battery charging! Use
appropriate gauge and insulation wire type, and put the
fuseholder in a convenient place.
***SEE
later in this posting about the negative wire!!
Have the jack located where you won't have excessive wire
lengths....or other problems such as pulling on your
clothing;....when you plug in your heated clothing and mount and
dismount the bike.
For the RIDER who happens to have an appropriate fairing,
consider the rear of the fairing left pocket, if it has
one;....as MOST heated vests have the VEST connection on the left
side, AFAIK. If you put the jack in such a place, be SURE
nothing put into the compartment can cause a short circuit.
Shrink tubing or other good insulation is usually a good
idea. Black
electrical tape is not a good
idea...it tends to unravel over a long time period, besides often
making a sticky mess after some time.
If you have a fairing, and a passenger along that wants heated
clothing, probably TWO SEPARATE jacks is best, with the
passenger's being in the stock area that BMW provided...at the
seat lock area on the left side (obviously this does not apply to
those with rear seat locks such as a ST model). Some
folks install three of these jacks, and run all sorts of
electrical devices from them.
The stock position for many BMW airheads was at the left side
seat lock area and BMW had a thick sheet metal bracket just for
the plug. See any BMW with one of these, they were standard on
many models (especially RT).
The part number for the jack has been changed now and then, for
example it was 61-13-1-243-661, now is 61-13-1-379-719; and the
folding weather protecting cover for it was 61-12-1-243-662,
which became 61-12-2-393-574. Better check those numbers, may be
wrong these days. Old style jacks used either no
cover, or a rubber cover, and some versions of the jacks have a
plastic flexi cover, that will eventually break.....the better
type, K models, had a hard cover, spring loaded. Be
very careful you get the type you want, and that is reasonably
weatherproof.
For models like the R65 the fuse box is on the right side of the
frame and could be modified for an extra jack.,,,,perhaps not so
convenient for clothing. That fuse box...on rear of the
box...might be a convenient place to mount a heated clothing
thermostat.
Be cautious. You do NOT want any
wire, connecting to the jack from your clothing, becoming
disconnected....and flying into your rear wheel!
I suggest NOT fastening the jack to the handlebars, for constant
wire movement problems, and perhaps safety problems. Could be
done correctly, of course.
One CAN make a bracket, or maybe purchase one, and mount a
standard cigarette lighter jack someplace similar. Most of these
jacks have a somewhat flimsy outer metal shell that acts as the
'nut' and must be installed securely and electrically correct for
grounding. I do not like them for their poor grounding, and the
FACT that the center contact is fairly poor, compared to the type
of gripping contact for the stock BMW plug and socket. Some
of these cigarette jack shells do have a grounding spade tab.
Whatever you do, do it neatly, fuse the positive lead, and have
the wires and fuses such that they won't
short circuit or fray from
vibration. If the wires are substantial in size, you could
go as high as 30 amperes, which is about the limit for the jack
and plug. Don't willy-nilly go to large fuse sizes if you
have no REAL need. Don't try to have high current
capability if you wire this through the ignition switch, that
switch is not rated for much more than it carries already.
***ONE
special precaution:
When you attach an
accessory socket...or anything electrical really...to your
airhead... you may or may not be contemplating the connection of
its grounding or negative wire to the ACTUAL battery negative
POST. I feel that it is BETTER, over-all, to NOT connect
this accessory jack...radio....or whatever....directly to the
battery negative post. While electrically it may be a tiny bit
better under SOME situations, a problem can come up, so I am
advising NO direct connections to the battery negative
post.
Here
is the reasoning:
It is STANDARD practice on a BMW airhead to electrically
disconnect the battery, when you need to do such as remove the
outer timing chest cover; by removing the battery heavy negative
black wire from the transmission speedometer cable hollow vent
bolt. This thin hollow bolt is located at the right rear of the
transmission. That bolt has a triple function; it grounds
the battery to the engine, it vents the driveshaft and
transmission, it secures the speedometer cable. Thus,
if you have something connected directly to the battery negative
terminal that is, in itself, grounded, such as the shell of an
accessory jack...you are defeating the purpose of disconnecting
the large gauge battery wire at that hollow vent bolt....and can
seriously damage your diode board, as one example, upon removing
the front cover. By grounding your accessory jack to the
FRAME, not the battery negative terminal, you avoid problems.
HINT: It is convenient to cut a wee
slice out of the battery lug located at that speedometer cable
point...so the vent screw only needs slight loosening. A
small slice is all that is needed. Be sure your hollow bolt
has the washers on it. The battery lug goes between the
washers.
You
MUST disconnect the ACTUAL battery power BEFORE removing the
front engine cover. IF you disconnect at that hollow
screw point, and SOMETHING ELSE is connected to the battery
negative post itself (a radio, charger, cell phone, OR accessory
jack!...or cigarette outlet negative wire; and, 'that something
else' provides ANOTHER path to chassis ground for the
negative....well!....>>get the idea? You really do
NOT want any other ground paths when removing the front cover,
nor when working on the bike's electrics.
With
SOME accessory sockets (yes, even some of the DIN German type),
the shell is insulated, with others the negative is part of a
metal shell, and if it is mounted in the plastic of the fairing,
there MAY be no problem. So, no matter what the situation, and
they vary, be sure that the negative connection is to the frame,
not the battery negative post, UNLESS you KNOW what you are
doing!
When I post something to the Airheads E-mail LIST about
electrical work you may read that I said to remove all
wires at the battery NEGATIVE "POST"...this ASSURES no
ground paths, no matter WHAT someone did with
wiring. It is a safety precaution for me to say it
that way.
So, I suggest you not add things to the battery negative post,
and instead find another nice grounding point for your accessory
jack. Look for most anyplace on the bike that has a screw or bolt
to the frame, and/or maybe one or more brown wires connected at
that point.
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revisions:
04/03/2003: editing for clarity.
02/06/2004: minor editing
11/30/2005: updated
01/24/2008: updated for clarity