INSTALLING AN ACCESSORY ELECTRICAL OUTLET
on BMW Airhead Motorcycles; recommendations for
Hella-DIN adaptors with USB output for GPS, cameras,
and other devices for ANY BMW motorcycle.
© Copyright, 2013, R. Fleischer
Recommendations for DIN adaptors to USB connectors; also wired versions : It is not easy to find these, and especially for good reliable ones with plugs that do not release from vibration, etc....and at a reasonable price. I tested the following products for temperature, output, regulation, and some other things and the price is reasonable. These connect to your bike's electrical system, either to the battery, or to the system after the ignition switch, or simply plug into an existing DIN jack (or, one you add) on your bike. These adaptors I recommend are NOT cheap cigarette lighter socket plugs but quality Hella-DIN types, that grip well too. All have 5 volt USB type outputs. Single and dual versions, either with 2.1 or 3.3 ampere ratings for output. NOTE! These items have a tiny current drain when plugged-into your bike. Thus, if you intend to leave such a type connected all the time, I suggest you wire the socket into the bike so power is ON to the adaptor socket only when the ignition switch is ON; unless you use a Smart Charger most all of the time when not riding the bike. You could always install an on-off switch too. I have thoroughly tested a number of these. Both the 3.3 ampere and 2.1 ampere versions have a no-load drain of about 0.006 to 0.007 ampere. The standard 5 volt USB output is solid, well-regulated, and was tested between 11 and 15 volts input at the DIN plug. My above tests are ONLY for the BurnsMoto.com items, made by Cliff-top.BurnsMoto.com, previously, was the only source I found in the USA. The product is made in Taiwan by Cliff-top who have some models that are not seemingly available in the USA, but BurnsMoto.com have what you likely need. I fully tested several of their products.
There is nothing very complicated about installing the
standard accessory outlet socket onto almost any
Airhead. The female accessory socket & mating male plugs are
available from many sources ...and
various styles of these sockets & plugs are available; even 90° plugs.
However, there are some
hints & precautions you may not know about, that can save you some hassles & money.
An accessory outlet should have, or you should incorporate, a FUSE in the POSITIVE (+) lead. That lead (wire) is usually red; this is the lead that goes to the CENTER outlet jack contact. The STOCK fuse size was 8 amperes, but most accessory outlets are good for 16 ampere fuses in the circuit if you need that much power. Accessory outlets should be wired directly to the battery + terminal unless you have a REALLY GOOD reason to wire it through the ignition switch. I suggest wiring the + lead via a fuse directly to the battery, thereby avoiding having to have the ignition switch ON. The accessory outlet (can be used as an INLET for a charger) socket (jack) is an excellent place to plug in your battery charger (or heated clothing); thereby avoiding problems with alligator clips, sparks, etc. You wouldn't want the key ON during battery charging, so wiring the outlet to the ignition switch output is not a great idea (unless to the input side of that switch, for a nearby mounting of the outlet). Use appropriate gauge & insulation wire, & put the fuse holder in a convenient place. Some folks have more than one accessory outlet, and one might be 'live' all the time, for some purposes.
***SEE later in this posting about the negative wire!!
Have the outlet located where you won't have excessive wire lengths....or other problems such as long wires pulling on your clothing when you plug in your heated clothing; mount & dismount the bike. Some folks will have two or even three of these accessory sockets, some have one direct to the battery & others through the ignition switch, for such as a GPS, clothing, etc.
For the rider who has a 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. If you put the jack in such a place, be SURE nothing is put into the compartment that can cause a short circuit. Shrink tubing or other good insulation is usually a good idea. Black electrical tape or worse yet, duct tape....are not good ideas...they tend to unravel over a long time period, besides making a sticky mess after some time.
If you have a fairing & a passenger that wants heated clothing, probably at least two separate outlets is better, with the passenger outlet being in the stock area that BMW provided. Some folks install three of these jacks & run all sorts of electrical devices from them. The stock position for the standard accessories jack on many BMW Airheads was at the left side seat lock area & BMW had a special thick sheet metal bracket just for this outlet. See any BMW with one of these, they were standard on many models (especially RT). The part number for the socket, often called a jack, has been changed now & then. For example, it was 61-13-1-243-661, then 61-13-1-379-719; & 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 by now. Old style sockets used either no cover, or a rubber cover, & some versions of them 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 & that it is reasonably weatherproof. There are 90° PLUG assemblies on the aftermarket, so the plug goes into the socket without sticking out very far. For models like the R65, the fuse box is on the right side of the frame & could be modified for an extra socket.,,,,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 outlet from your clothing, becoming disconnected....& fly into your rear wheel!
I suggest not fastening the socket to the handlebars, due to possible constant wire movement problems, & perhaps safety problems. Could be done properly of course, & BMW included such on some models, like the K-LT & other bikes where BMW installed a jack on the bars trim piece. BMW also usually installed one or two other jacks near the ignition coils on those K-LT models. Thus, those K models came with 3 outlets/inlets.
One CAN make a bracket, or maybe purchase one, & mount a standard cigarette lighter jack someplace similar. Most of these 'cigarette' jacks have a somewhat flimsy outer metal shell that acts as the 'nut' & must be installed securely & electrically solidly correct for grounding. I do not like them at all because of their poor grounding, & that the center contact is fairly poor, compared to the type of gripping contact (DIN plug, DIN jack) for the stock BMW plug and socket. Some of these cigarette jack shells do have a grounding spade tab, ....but mostly that ground tab is from the shell which acts as the nut; but those with the tab from the inner piece are much better. There can be a problem with the shell always contacting ground. I get into this a couple of paragraphs further down.
Whatever you do, do it neatly, fuse the positive lead, & if you install in-line fuses, install the 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 absolute limit for a jack & 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. Relays are mostly not used to due contacts problems for accessory sockets.
***ONE special precaution:
When you attach an accessory socket...or anything electrical...to your Airhead (this can apply to many other bikes too)... you may be planning to make the connection of the grounding (- wire) to the ACTUAL battery negative POST. It is BETTER to NOT connect an accessory jack...or radio....etc. directly to the battery negative post. While electrically it may be a TEENY bit better under SOME situations, a problem can arise, so I am advising NO direct connections to the battery negative post......and....the reasons follow:
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. The normal method to disconnect the battery is to remove 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 & transmission, & it secures the speedometer cable.
The PROBLEM occurs this way: If you have something connected directly to the battery negative terminal such as the shell of an electrical outlet socket; and some shells or outer parts are grounded by their mounting...then you are defeating the purpose of disconnecting the large gauge battery wire at that hollow vent bolt (or, other place someone may have connected it to, such as the frame or transmission). You can seriously damage your diode board, as one example, upon removing the front cover. You may be leaving the system powered, while you think it is not, & there can be real nasty expensive problems.
By grounding your accessory outlet to the FRAME someplace, & NOT the battery negative terminal, you avoid such problems. With SOME accessory sockets (yes, even some of the DIN German types), the shell is insulated; with others the negative is part of a metal shell, & if it is mounted in the plastic of the fairing, there might be no problem. No matter what the situation, & that varies, I usually suggest you make all accessory (-) connections to the frame, not the battery negative post, UNLESS you KNOW what you are doing & WANT it that way! To restate my advice: the accessory socket should NOT be grounded at the battery negative post.
When I post something on-line about electrical work you may read that I say something like: "Remove all wires at the battery NEGATIVE POST". This ASSURES no ground paths, no matter WHAT someone did with the wiring. It is a safety precaution for me to say it that way, & in line with the above paragraphs now you know why.
SO: I suggest you not add things to the battery negative post; instead find another grounding point. 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. Along the backbone is at least one such place that BMW themselves uses, usually near the ignition coil(s).
HINT: It is convenient to cut a SMALL slice out of the battery lug located at that speedometer cable point...so the hollow vent bolt only needs slight loosening. Be sure your hollow bolt has both washers on it, which will prevent spreading of the lug. The battery lug goes between the washers.
11/14/2008: incorporate all prior revisions, and update for clarity
05/02/2011: more darn clarifications, and some cleanup
05/06/2012: Clean up a bit more
09/09/2012: A bit of clarifications here and there, change emphasis here and there, add QR code, change Google ad layout
12/14/2015: Clean up. Improve meta-codes.
04/30/2016: Final on the above.
07/31/2016: Add Optimate.
© Copyright, 2013, R. Fleischer
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Last edit of THIS page: Wednesday, August 10, 2016