I've searched the forum without luck, though I'm sure I'm not the first person who's had this problem.

Bike is an 18 FXBB Soft tail.
Can anyone confirm that the three wires running to each tail/signal light housing are;
Blue - Run/tail light
Violet - Turn & brake light
Black - Ground

 

Yes, that is a standard color code for domestic HD run/turn signal lights. I did a quick search just to be sure and it was easy to find using google images.

I highly recommend you get a shop manual with wiring diagrams and a good meter if you don't already have them if you are going to go DIY with your new ride.

Good luck.

 

I have the 18 FSM. I'm adding a fender mount run/brake light and retaining the side mount run/stop/turn lights. I assume I need to run jumpers from both violet wires (each side) with one-way diodes for brake light function in the fender mount light when one or the other signal is activated. Does that sound right to you???

BTW - THANKS! I was beginning to wonder if anyone was going to chime in.

 

Okay, I think I have this now. After discarding my focus on trying to make this work from the existing wiring and going back to wiring basics, it became obvious I'm trying to make something simple into something complicated.
Very simply, I'll be using the run and ground wires from the existing rear harness. I'll be adding a dedicated (new) wire for the brake function. I was dreading trying to find that brake light wire buried in the main harness and tap into it. Some more searching reveals that it's not as "buried" as I expected. It's actually quite accessible. Not predicted to get above 20F here the next two days and my work space is unheated, so it'll likely be a couple days till I get to it.

Sometimes I get too focused for my own good.

 

I am trying to do the same thing....could you possibly send pics of where you tapped into the wires?

 

I haven't actually done it yet. Too cold here. Saturday it should be a balmy 40F and I can get to it.

I did connect the other wires (blue & black) inside the left blinker housing. The brake light wire (blue w/red) should be attached to the input side of the tag light connector under the seat. Why it is, I have no idea! Only one hot and one ground come out of that connector (2 blk. wires). NOTE that I said SHOULD. I have not had the opportunity to look at my own or put a tester on it yet!
This is not the light I'm using. Not even the style light I'm using. Not the same functions. It is however the best photo I've found online of the brake light wire. THANK YOU Cadence Motorsports! Just ignore all the big blue hardware store connectors. This is Cadence Motorsports photo I borrowed. NOT my own! Here is a link to that whole install of theirs.


Are you relocating your tag mount? That was the primary reason behind me doing this! If so, a right side signal stalk, flipped over, fits the left side perfectly and gets rid of the short stalk + tag bracket that comes stock. $17 @ the dealer in your particular matching paint. I'll post the full install when I'm able to get to it.

 

I am mounting the Blackmill License Plate relocation kit, but also adding the Zeel Design fender mount light. I want the existing lights to still be running, brake and turn, but the center fender mounted light to just be running and brake. Like you I was not sure if i needed to tap into both of stalk mounted lights.

I ordereded new Black stalks, they were like $13 each at Surdyke.

 

IF you are keeping the stalks and signals stock, only the left side is needed. That replaces the side tag mount which is incorporated into the left stalk, but thirteen bucks won't break the bank!
If I hadn't already gone down the path I have, I'd just run three (new) dedicated wires from under the seat. Blue (run) Blue w/red (brake) Black (ground). It would make a much cleaner install and avoid future problems when the fender has to come off for any reason. I'll probably go back and clean up what I have done and go this route.

Go to a home center / hardware store and look around the zip tie display. You should be able to find "mounting pads." Use them to tuck the wires out of the way under the fender. 1" squares for attaching zip ties with an adhesive backing. Just make sure you have the fender CLEAN before sticking them on and place your wires so there is no chance the tire will contact them. Here's a link to em @ Lowes.
Your bracket / light probably has tag lighting. If not, go to any auto parts and pick up a set of cheap LED tag bolts. Pretty neat gadgets. The drawback is the wires run though the bolts (of course) so if you ever have to remove the tag, you have to cut the wires.

 

Yep. I used the zip tie mounting pads when I installed the Custom Dynamics flashing tail light with our tag mount.

Here is a link to the install with the image already listed above. While not the best method, it works for people who don't want to drill a hole through their fender. It also has the added benefit of you being able to remove the fender without removing the wires.

Cadence Motorsports Flashing Tail Light Wiring Example

 

THANKS! Especially for that photo! Hope you don't mind me borrowing it.

While I'm unable to spend more than a few minutes in the garage or concentrate on anything while there (it finally got up to 16F by 2PM today). It's been difficult to picture what's where from schematics alone. I do have the fender in the house and plan to rewire it tonight and clean up the mess I made trying to figure out how to make it work with the existing rear harness. Seeing you use those tie blocks in your tutorial was a big piece of mind after I'd already settled on trying them. I had a T/L wire short out from rubbing the tire years ago and went through a box of fuses before figuring out where the short was!