I wonder how much of a difference these really make to the overall
light
output.  It seems to me that you are still using the 15+ year
old
small gauge wiring and that the only thing that you are really
doing is
by-passing the high currently going through the headlight
switch thus
saving it and installing brighter bulbs to get more light
output.

It would be interesting to get a back to back
comparison of actual
voltage at the headlight before and after
installing the relays - I would
suspect there won't be much of a
difference due to V=IR losses.  In
other words the more currently you
put through a wire the more voltage
loss you get - these old wires
will have a lot more resistance than new
ones.

Assuming
20A of current through 2m of wire:
14 gauge (new)  = 0.33 v drop

Adding some corrosion in
there would double or triple the
resistance easily resulting in a 0.7 v or
so drop

http://www.stealth316.com/2-wire-resistance.htm
explains a lot
about this

What I have done is get some 8ga wire
and went
from the battery direct to behind the grille (install a fuse fuse
at
the battery!) then I installed some water proof 30A relays behind the
grille one for low beam, one for high beam and one for my rallye
lights.  I used the original headlight connectors to trigger the
relays and have new 12ga wiring to new terminal housings that plug
into
the back of the light.

Now when I turn on the lights
there is
almost no voltage drop between the battery and the lights
and the lights
are much brighter again - no current through my
headlight switch or
ignition switch - factory wiring is 100% uncut
and can be turned back to
original.

Using the above
formulas and averaging at 10 gauge
(most of the wire is 8ga - 30cm is
12ga) would result in a 0.1 v
drop.

When you have only
13.4V to play with - every
little counts!

David
Marshall

http://www.hasenwerk.ca
http://www.fastforward.ca

Box
4153, Quesnel BC, Canada
V2J 3J2

On Mon, November 5, 2007
10:01, Stephen Grisanti
wrote:
> We ordered one of these on
special last month and
> Sunday was the day to install it.
We’re leaving for
a
> week in the Smokies soon and with the
recent time
> change better lighting in the mountains will be
most
>
welcome. You can see captioned pix of the job at:
>

> http://picasaweb.google.com/bike2vcu/HeadlightUpgrade
>

>
> It took about 90 minutes from start to finish.
The
> biggest change seems to be in the low beam.  When the
> lights are on you can actually see the light cast on
>
the
pavement in front of you.  It’s not real cheap but
>
improved night vision will be well worth it, and the
>
circuitry
upgrade to relays will help ease my mind
> about
melting the light
switch.
>
> Stephen