Overview: Flushmount turn signal

Also happening during the 2 weeks of “While I’m in there, I might as well do this”, I decided to install 60 some odd LED’s in the rear body work, to replace my current, stock turn signals. This project is probably almost 3 years in the making now, and I’ve finally gotten around to it. I saw a fellow by the name of Travisty on newninja.com do this to his bike, and wanted to do the same, but with a slight alteration.

First, the fender: Move the license plate to the fender:

Wire LED’s together, glue into fender with CA glue – the best stuff ever!

Tape it up with electrical tape to keep reflections down and LED’s stuck where they’re supposed to be:

Closer look:

All lit up:

Now the body panels:
First make a template out of lexan. It’s easy to design and decide on the layout you want to use, instead of accidentally drilling a hole in the wrong place:

Use a punch to put little divots in the body work to make sure your drill doesn’t wander. Pre-drill the holes with a thin drill and make sure they are where you want them before bringing out the big drill bit.

At this point I got tired and quit for the night. Sleep, work, eat, and back to wrenching:

I found these LED’s actually not to be 1.5v, but to burn beautifully at 1.9V, all the way up to 2.3V and start to turn reddish above that. They would get dimmer and redder as you approached 3V at which point they would pop almost drawing 5amps before giving up the ghost… This made things difficult for a multitude of reasons: I didn’t have an LED flasher relay, so I was trying to make the relay function (requiring a certain amperage), while trying to make the LED’s burn correctly. I could EITHER pull enough amps to make the relay work, or to let the LED’s burn, but not both, because the relay couldn’t get enough juice to make a solid contact to allow the LED’s to burn to full brightness.

The problem was compounded because the bike produces about 14V at idle (perfect), but almost 15V above 2,500rpm. With more time and more resistors I could have made this work, but I didn’t have the time, and in the end, it would be hack, and I don’t like that. With the Resistors I had the only option was to unsoldier everything and add a resistor to each one individually. I had neither the time or desire to do this, so i decided to scrap it and go with pre-resistorized LED’s from China.

How did I have it layed out? For the back sides I drilled 3 rows of 7 a piece, yielding ~ 1.7v per LED. Each row I had hooked in series to get to 12V (should have calculated on 14V), and the sides I had 2 rows of 8 LED’s in series ~1.5v per LED, not enough to even make them glow. On the sides then I decreased each series row to 7 LED’s (1.7v) and put 2 in series with a resistor. Essentially then, I had 6 rows of LED’s wired in series, which I then all wired in parallel. I hope that makes sense.

Needless to say, it was ugly and hack, and didn’t work anyway. It would probably have worked with the LED flasher relay, but I didn’t have time to get one (no local auto stores had one in stock – at least not a 2 prong and I wasn’t gonna futs the system into a bigger hack state my hacking the relay). Since this is the failed attempt, there is no step-by-step. I’ll do that for the much better designed – a copy of Travisty’s design. Why did I try and do it this way? To open up some amps in the system. Not because I need them, simply for the idealistic achievement of pursuing efficiency. In other words, just to do it.

Math: In a no-loss system the incandescent turn signal bulbs draw 300mA/piece x 6 = 2.14A total. Why 6 bulbs? There are only 4 turns signals… Ah, but the front turn signals have a second element each which function as running lights, unless I have my motos confused here. For 4 bulbs the energy savings would be: 1.4A total. Watts = Volts x Amps. W=5, V=14. Solve for Amps. K, enough jabbering.

Here are some pictures:

So, they look awesome and I want to continue with the project, but I can’t make it work…. Time to wait for the LED’s from China…. After 2 weeks the LED’s arrived, and we go:

K, so the new LED’s came in, and the physical bulb was twice as long as the previous LED types which means they stick out from the body work a bit more, but they cost about the same, and I could always shave them down later (luckily the actual light emitting part is very close to the base of the led).

First, I test-mounted an LED to make sure it was going to fit. Turns out these 5mm LED’s are actually 5 mm, not 4.5 like the last ones. Which meant I had to re-drill all the holes. Luckily, since all the holes were already where they were supposed to be, opening them up an extra 0.5mm each took only 5 min. You can also see some residue from the liquid electrical tape I used during the first go-around:

Here they are all dry mounted, in the end, I decided not to glue them. With the extra length of the LED’s, they are pretty difficult to remove, so it didn’t seem as though they’d need glue:

You can see how far they all stick out:

Although not quite as smooth, and a bit more ugly, they are slightly more noticeable, which is kind of the point, so I’m not fussed. OK, what’s the backside look like? A mess, that’s what:

Some soldierings and the original plug + wires from the stock turn signals:

And some liquid electrical tape to make sure everything is covered. I later also covered this in regular electrical just to provide some more structural support to where the itty-bitty wire comes into the big bundle. I usually use heat-shrink, why not in this case? Because the diameter difference between the two wires is too great for a single piece of heat shrink to shrink to. This is one place where you definitely DO NOT WANT water leaking in. I also didn’t want to waste a bunch of heat shrink building the smaller wire’s diameter up…

Also, this works with the stock turn-signal relay, which I’m happy about. I will be testing them with the new timed relay, as soon as it comes in, but for now, I’m just happy they work.

Here’s a video:

Hope you enjoyed the ridiculously long article!


About Dandooligan

Dandooligan CO, United States Every ride spurs the yearning for another and as such, has pushed me to adopt the riding lifestyle and all of it's challenges. This blog concerns those challenges from bikes to gear, media about bikes, and maybe even some psychology/sociology on the subject as well. Dandooligan, a mash-up of Dandy and Hooligan, both very important parts of me and my outlook on life. I'm also known as Spooph


  1. OMG! I am officially jealous of your wiring and soldering prowess! This makes my little kill switch project look like child’s play. You are the man!!!!

    I wish I had the patience for something like that.

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