I just purchased a set of 55w Aux. lights (Halogen bulbs) with plans to put them on my dyna..

As soon as I opened the box, I realized that there is a good chance that these draw to many amps for my dyna.


Anyone input would be appreciated!

 

I bought my '07 SB in March and it had the lights already on it and no probs with Volt reg or anything else yet, although I will be switching all the bulbs on the bike to LED (to save some amps) and add a quick detach fairing with radio and speakers soon.

 

they will be okay . just use a relay in them about 20 amp.

 

I used a 30A relay and a fuse, no probs for the last 2 years. I'd suggest to turn the aux light on and off while the engine is running so you don't drain the battery while the engine is not charging it and to still give as much power to the starter motor as possible.

 

Hmm... I'm really new to this. I've wired up offroad lights on my truck, But have never ran a relay. I just ran the lights, to a toggle switch, to the battery.

does anyone happen to have a simple diagram laying around that I could look at to get an idea? I'm Really bad at electrical..

 

What model/year bike you're talking about?

Generally speaking, most H-D models have a 32 AMP electrical system.
Here's how to calculate your power consumption:

volt X amp = watt
so
watt / V = amp
for the passing lights: 110 / 12 = 9.1 amp

Headlight takes 55 watt = 4.6 amp
Running lights take 5 watt each = 0.8 amp
Directional lights take 21 watt each = 3.5 amp
Brake light takes 21 watt = 1.75 amp
Rear light takes 5 watt = 0.42 amp
Etc.

With a 32 amp system you will be good.

Here's a passing lights wiring diagram.
Some options:
1. To run passing lights independently: splice battery + or ignition switch powered 12 v wire to switch in diagram
2. To run passing lights with low beam: splice low beam 12 v feed wire to switch in diagram
3. To run passing lights with high beam: splice high beam 12 v feed wire to switch in diagram

 

Wow that was quick. It's a 2007 Street Bob.

Thanks FXD2003Rider

 

You're welcome.

Some additions:

For option 1 either connect to the battery + pole or use one of the the orange/red wires from the accessory plug (pin 1 or 3) under the seat (see image below for the plug parts to use)
For option 2 use the yellow low beam wire in the headlight bucket;
For option 3 use the white high beam wire in the headlight bucket

 

years ago i had them on my bike tapped them under the tree actually worked great!

 

Damn!!! That is exactly what i was planning on doing. I was so stoked on doing that because I have never seen in done before. Well now I may have to reconsider... maybe i'll mount them where the forward controls would go, or maybe even on the bottom of my T bars. Hmm...