Lights are an important accessory for any MOD bike. Some just bolt them on for aesthetics,
but to my mind, they have to work. I have eight lights running on my Vespa P125X.
READ ON: You can do this even if right now you have no idea how electricity works, but you
have to be willing to learn a bit. Trust me, there's enough info on the web to figure it
out. I didn't know anything when I started, but with google and advice from friends
(which I'll share here), you can get this project done.
I used these resources:
Lambretta Club of Great Britian - Wiring up extra lights
http://www.lcgb.co.uk/workshop/spotlights.html
Relays
http://www.bcae1.com/relays.htm
Here's how I did it.
Part 1: Battery
requirements: 12 volt battery: sealed gel-cell
My set-up has a battery placed in the glovebox. I run all my auxilliary devices from this
battery. Get a sealed, gel-cell 12 volt battery. A sealed battery offers the safest option
for your glovebox - even if it you secure it, and you should, it will probably
bounce around a bit (tho they are heavy), and you do not want anything you fill, like what
you might have on your bike already (if you have a P-series or other later Vespa or any
Stella, etc.). I got my battery at a local Batteries Plus store. Get a battery with as
many "amp hours" as you can fit in your glove box. This point is pretty obvious: more amp
hours = a longer running time for your lights (and the more lights you have on your
bike = the more amps pulled from the battery. You're not going to have a very long life
with this system, unfortunately. I only get about half-an-hour of run time).
Part 2: Wiring
requirements: 20 amp blade fuse and inline blade fuse holder
Toggle switch
12 volt, 30 amp relay (or relays... I used three)
14 awg (American wire guage) wire - get at least two colors, black and red would be typical.
Wire cutter/stripper/crimper
14-16 awg female disconnects (blue-colored insulation)
14-16 awg male disconnects (blue-colored insulation; if needed)
wire connectors - I purchased yellow-colored connectors, which are a bit larger
Now we really get into it. Remember - you are doing this work at your own risk. I am not
an electrician, I don't know any electricians... this is simply how I set-up lights on my
bike and it worked for me. Do not hurt yourself! And you can hurt yourself!!
My battery came with male spade connectors, so I placed a female connector on one end of
the fuse holder. It's quite easy: strip off a bit of wire sheathing, place the wire in
the connect, put your crimper tool over the plastic part nearest the spade, and squeeze
hard. There you go!! I had a lot of trial and error, and found that XXX brand connects
from Home Depot work best at staying on the wire. The connects I bought from Auto Zone
don't crimp as well, and i had to tape them in place after crimping. I also bought some
GB brand connects from a local Do-It-Best hardware store, and while they crimp on just as
well as those from Home Depot, they are for some reason hard as hell to disconnect. Which
isn't a bad thing, unless you are just practicing and need to move wires around.
Next we power the relay. If you haven't checked the resources links above,
READ THIS PAGE ON RELAYS before you start wiring. If you don't know anything about
relays - don't worry, I didn't have a clue when I started - it will help make the
following understandable.
OK, so the relay has four sides, labelled 30, 85, 86, 87. There is typically a pole in
the middle, labelled 87a. For this application I did NOT use pole 87a. Pole 30 is
perpendicular to the others. This is the pole that you power the relay with. Take a
length of wire (not long, 6-12" or so should do it, depending on how long your fuse holder
wires are - you can go longer and trim later) and put a female connect on one end. Take
this end and plug it into pole 30 on the relay. Next we will prepare to ground the relay,
so - if pole 30, where the relay is powered, is the "bottom," take one of the "side"
poles - 85 or 86, it doesn't seem to matter (I used 8x for this, I think the important
thing is to be consistent as you add relays) - and add a length of wire connected with a
female connect, like we did to power the relay. In a typical auto installation, ground
will be BLACK. The ground wire on your Vespa should be BLACK. So I did mine in black as
well. Whatever color you choose, it's a good idea to choose separate colors for ground
and everything else. This way, it's easier to remember what wire is responsible for what
and you won't accidentally mix them up and create a huge problem for yourself (Red, btw,
would be a popular color for the positive - my battery has a red block indicating the
positive terminal. In my own installation I ran out of red wire and switched to blue to
run the lights. But the relays are all powered with red-colored wire). We'll wire the
other two poles in the same manner - the pole opposite the ground will be used to connect
to the switch, and the pole opposite the power, or at the "top" of the relay, will be
connected to the lights.
Next, by wiring the relay to the battery via a fuse holder you get what sites will call
"fused power". I chose to to protect my switch and relays from this same fuse, so this
is how I did it: strip off some sheathing from on of the wires from the switch (if you
have a three-way switch, as I do, use the middle wire), the wire from the relay, and one
wire from the fuse holder. Twist these together, then put them in a wire nut and twist
some more. I purchased wire nuts that are a step up in size from the wire that I was using
so that I could put multiple wires in them. I taped the wires and nut to give me a bit
more protection. Now connect one of the outside wires from the switch to whatever pole
you've chosen on the relay (I used 8x). Finally, connect the wire from the relay to your
light.
NOTE ON LIGHTS AND GROUND: lights have to be grounded to work! Many lights are sold as
"self-grounding," which means the ground wire from the light's wiring harness is returned
to the light's body. If you have lights with only one wire coming from them, they are self
grounding. Lights with two wires, then, obviously have a positive and ground (for many of
the smaller lights of this sort, it does not matter which is which, as long as you wire it
by choosing one for positive and one for negative. However, even a self-grounding light
still has to come in contact with a grounded source in some way. I found that I had to
wrap a bit of wire around the light's assembly - a screw, a bolt, whatever - and run that
wire to the battery negative.
Take the ground from your lights, the ground from your relay, and add a length of wire -
you'll use this to connect to the battery. Take the three wires and strip some sheathing
off and twist them into a wire nut, as we did above.
Last step: connecting to the battery. Get connectors that will work for the battery you
bought! As I said, mine has male spade connectors, so I connect my wires to it with female
connects. Put a connect on the open fuse wire and a connect on the open ground wire (from
the wire nut group). Plug in! Flip the switch! If all goes well, you have lights!
NOTES:
1) depending on how long the wire is on your switch, you might be able to go directly from
the switch to the relay, just put a female connect on the switch wire and plug in.
2) you may want to learn how to solder, if you don't already. It's not really something
you can learn online, although there are sites that show you how to do it. They're helpful
to get the gist of it, but if you're soldering for the first time I think it helps to have
someone who knows how to do it show you how, or at least look at your soldered wiring and
let you know you did it right [thanks again, Jesse].
3) I haven't figured out a way to keep the battery charged, so I just disconnect the wires
to the battery, pull the battery out of my glovebox, and use a trickle charger
to re-charge my battery. A trickle charger is handy to have anyway, if you don't already. You can use
a trickle charger on your bike's regular battery as well, particularly helpful through the
winter when your bike might be sitting longer between rides.
Now experiment. If you have a three-way toggle switch you can use the other wire from the
switch to power a separate set of lights, if you want. Mine are set up so that if I toggle
in one direction I get a four lights and if I toggle the other direction I get eight lights.
I had to put a third relay between the two to get this application to work. Be creative.
Write me at jj@modchicago.com if you have any questions.