A number of Atom owners have purchased replacement lights due to problems with the Brammo-supplied lamps. Those problems include the bulbs popping out, the housing cracking, and intermittent lamp operation.

One of the most interesting replacement options are the River Runners (via the Internet Archive) lights. These were offered as a group buy on the Atom Club Forum (now ariel.club) between 2007 and 2008.

In my opinion, these are very attractive lights, and I ordered a set and installed them on my Atom. However, for other reasons, my Atom didn't see much use in 2008. In the meantime, another Atom owner reported that the River Runners he had installed on his Atom had experienced a number of failures. As these lights are no longer available (they're being replaced by a new model which the web site (dead link) shows as "Coming Soon"), I wanted to take some steps to make sure mine wouldn't fail.

Based on the description of the failure by the other Atom owner, it was probably caused by something inside the light breaking loose under extreme vibration. He described the aftereffect as something rattling around inside the light. Unfortunately for purposes of repair, these lights are sealed and it is impossible to open one without destroying it. Thus, anything done about the problem needs to be done before the lights fail.

I managed to purchase a second set of lights from yet another Atom owner who had purchased them but never installed them. That gave me enough spares to be able to cut one open to see if I could determine what the failure mode was likely to be.

This page documents my findings and proposes a preventative measure to keep the problem from happening in the first place.

[picture of light]

This is what the "business end" of one of the River Runner lights looks like. This article probably won't apply to any other versions of these lights. The top of the lens is marked www.go-devices.com (then a a permanently "under construction" web site, now a domain that doesn't even exist).


[back of light]

This is what the back of the light looks like, with its mounting hardware. This is a pretty good system, incorporating a rubber ring to prevent the light from slipping. The only problem when installing on an Atom is that the large aluminum disc needs to have a piece notched out of it to accomodate the Atom's light stalk. I don't think this needs to be done on Rovers, the original market for this light set.


[first cut]

I made my first cut around the outside of the light, about 1/3 of the way toward the back from where the lens ends, and removed this piece of the housing.


[back of circuit board]

After removing the back housing piece, the back side of the circuit board can be seen. It is nicely coated with silicone for waterproofing.


[second cut]

In order to expose the component side of the circuit board, it was necessary to make another cut around the circumference. As you can see, the LEDs are mounted to a second circuit board which is also sealed with silicone.


[disassembly view]

Here you can see both the lens and the component side of the circuit board, to get an idea how things go together.


[close-up of circuit board]

This is a close-up view of the circuit board itself. You can click on the image for an even larger picture. There are a number of large components which could possibly break free under heavy vibration. The parts that are missing from the circuit board are used in the dual-intensity lights, used for the brake lights on the Atom.

Based on a quick study of the data sheet (Formerly National Semiconductor, now Texas Instruments) for the LM2576 regulator on the board, my theory is that the probable failure of the board is due to the inductor (the cylindrical part that is "pinched" in the middle) as that will completely disconnect the LEDs if it breaks off. It is also the most fragile and heaviest of the components on the board. The two capacitors (the other cylindrical objects) simply provide filtering for the input and output voltage and would probably not cause a total failure when removed.

Other than this oversight, the lights seem very well made. They should be completely waterproof, as claimed. The LEDs themselves are configured as 7 groups of 3 lights, so failure of one LED would leave still 18 LEDs operational. The data sheet says that the part will run from 7V to 40V, far beyond what is needed to meet the light's published spec of 12-24V. It also produces 3A of output current, more than enough to drive the 21 LEDs.

I should also mention that the vendor (Mobile Centre) was very helpful and repeatedly offered to refund the money I paid for these lights. But I wanted to use them, so I went ahead with this unsupported modification. I don't see any reason why the upcoming product would need any changes like this - it should be just fine out-of-the-box.


Now that I had disassembled the unit, I knew that my initial idea of injecting sealant through the hollow mounting bolt (where the wires exit the light) won't work. The back of the circuit board is already sealed and all the extra sealant would do would be to fill up a space that isn't part of the problem.

At this point, I decided I'd need to drill 2 holes (a fill hole and a smaller vent hole) in the housing, about 1/4" to the rear of the end of the lens, and inject a sealant through the fill hole until it starts to come out the vent hole. That will fully encapsulate the circuitry, and by using a black sealant, the holes in the housing should not be noticeable. Both the lamp area and the mounting bolt are isolated from this area by silicone sealant, so there shouldn't be any intrusion of the sealant into visible areas.

Another Atom owner with these lights pointed out that it is possible to pop the sealed inner lens + circuit board out of the outer housing, which made this process even more invisible from the outside.


[tools and supplies]

Here are the tools and supplies I'm using. At the top is a box of M G Chemicals 832B black potting epoxy. This is a product specifically designed for use on circuit boards. To the right is a 100cc syringe (no needle tip) in a mixing cup. Below that is a piece of cardboard with two slots for the center wires from the LED housings. Also visible are a roll of painters tape, a cordless drill with bits for both the main and vent holes (the tape on the bits serves as a guide to keep from drilling too far into the lamp housings), a prying screwdriver (used to pop the housings apart), a hobby knife (to remove any excess epoxy), and protective gloves.


[drilling the two holes]

First, remove the "Madonna" plastic cover from the back of the lights and make sure you have enough slack in the wires to be able to separate the two halves of the light. Using the prying screwdriver, gently place it between the colored plastic lens of the light and the black plastic ring. With a slight wiggle, the lens and the inner section of the light should pop out of the retaining ring. Locate the top of the light and drill a hole large enough for the nozzle of the syringe right at the top, about halfway between the front and back of the black plastic inner collar. Next to the large hole, use the smaller drill bit to make a vent hole. This should end up looking like this picture. Note that this picture was taken after the epoxy was injected and dried.


[tape the back as well]

Tape the back of the housings as well, both the inner and outer faces. Also, cover the top of the mounting arm so you don't get any epoxy on that, either.


[in place and ready for potting]

Now, use the cardboard to keep the inner and outer halves of the lights separated. Carefully cover the entire surface of the lenses with painter's tape - if you mess this up, you'll probably ruin the lights. Now, wrap the whole thing up with painter's tape so that it is held securely. Remember, you'll be adding some weight to this when you add the epoxy and you don't want anything to slip. You'll need to poke some holes in the painter's tape so you can insert the tip of the syringe into the larger hole in the housing. You'll also want to be able to observe the smaller hole - when epoxy starts running out of the smaller hole, you're done.

This would be a good time to place some cardboard on the floor under the lights, just in case you have dribbles.

Mix the epoxy according to the directions and after it is mixed, use the syringe plunger to suck it up into the syringe. Now, slowly inject it through the large hole at the top of the light housing. It will take a while to settle in the housing, so you could do the other one and then come back to the first one and top it off.

Let the epoxy sit undisturbed for at least 24 hours. After that, remove all of the painter's tape. If you were careful, you shouldn't have any epoxy dribbles to worry about. On the other hand, if you were like me, you can use the hobby knife to scrape the epoxy off. It doesn't adhere well to the black plastic of the light housings, so you should be able to get the edge of the knife under it and start peeling it off.

Also, make sure you don't have any protruding epoxy bumps at the holes.

Now, carefully feed the wires back through the central mounting bolt and snap the lens and inner sleeve of the light back into the outer sleeve. Rotate the light as needed so the top of the LED assembly is at the top of the housing.


All of mine came out well. In one housing, I did get some epoxy on the central hollow bolt that the wires go through, and I had to carefully pick at the epoxy to clear a path. On one light, there must have been an incomplete solder joint where the LEDs are soldered to the circuit board, as a little black epoxy "tear" is visible in the light if you look closely.

I have put over 5,000 miles on the lights since I made this change, under a variety of conditions (track, highway, off-road, etc.). All of the LED lights are still working, though I did have a H4 headlight bulb fail.