In my quest for a 1157 replacement that actually works in my bike(s), I think I am finally there. Hasn't been easy and I've been trying for almost 10 years now. The problem is that our bikes mount the 1157 bulb deep and at an angle, with the rear of the light coming off at somewhere around 45 degrees from the central axis of the bulb. And the license plate light is run off of it too, so it needs to be white and not red, or have a white component for the plate and red for the back. And the LP white portion has to shoot down from the bulb, at like, say, 160 degrees from the central axis, or almost straight down if you held the bulb upright in your hand. There just aren't many LED 1157 compatible bulbs that do all that. I think JG Cycles has one that will, but it ain't cheap. Another problem is that if you find an 1157 replacement, it may not be as bright as the real incandescent bulb.

So, LED technology progresses, and I tried a couple of these for $15:
https://smile.amazon.com/gp/product/B076YT323X/

They are white. Now, your tail light lens is a red filter. It only lets red light pass. Red bulbs have all the energy flowing through the red spectrum. White bulbs, like the incandescent bulbs and white LED's, have all the colors in them and only the red light portion passes through the filter to be seen. But we need some white component for the license plate, where there is no red filter at all in our tail light lenses. So we either need a bright white LED, or a red LED with a separate white LED set that points almost straight down (back).

I got the bulbs in today. Of course, they would not fit.


I drew an arrow where the problem is. That part interferes with the socket. The 1157 bulb is narrow there and fits deeper into the socket than that ridge allows. Well, to a man with a lathe, everything looks like a problem in roundness. I chucked it up by grabbing the bayonet end in the 3 jab and turned it down with a parting tool at the arrow until it fit into the socket. It's aluminum and I was pretty careful with turning it.

Here's a comparison:


The Sporty has the LED, incandescent on my bike. That is the regular running light. The LED looks to be slightly brighter than the incandescent. Here's the brake light:


A little bit brighter. I'm happy with it like that. My goal has been to save amps. Trying to run an EFI system on that Sportster is a biatch, given the 19 amp alternator. Every milliamp counts.

I chucked up the second bulb and got to turning. The bit grabbed it and destroyed it. Oh well. However, on the bright (PUN ALERT) side, I saw how the thing was made. There's plenty of meat where I was turning it. And if I had grabbed it by the distal end, it would take a lot more torque from the chuck jaws. I ordered another set. I'll turn one down for my bike.

 

Nice....And what did you do with the Headlights. That's where your real savings come in... A little over 5 amps......

 

You have to dremel the inside of the reflector so the bulb sits deeper. No big deal, I've done it a few times with no problem.

 

For the headlights, I have a Trucklight on my bike and I had a HD Daymaker on the Sporty, but it clouded up and I replaced it with this:
https://smile.amazon.com/gp/product/B01DZU30S0
at 10% of the cost of the HD unit. It was identical.

I didn't think of grinding out the housing. It's chrome plated. Kinda don't want to do that, but it's an interesting "don't raise the bridge, lower the water" solution for the lathe challenged.

 

Oh yeah, on the Sporty, "they say" that Daymaker and the identical one I have on it now won't fit this era Sporty. Well, kinda. I cut the cooling fins off the back of it until it fit in the bucket. Hasn't caused a problem.

 

Doc,

Get the LED circuit board from custom dynamics. It has a bunch of really bright LED's on a board that has two wires coming out of it that are attached to a brass socket that pushes/twists into the factory receptacle like a regular 1157 would.

It is one of the best modifications I made to my Heritage. It took only a minute or two to install.

I have an old thread around somewhere about it.

 

[QUOTE=I didn't think of grinding out the housing. It's chrome plated. Kinda don't want to do that, but it's an interesting "don't raise the bridge, lower the water" solution for the lathe challenged.[/QUOTE]

It's plastic, you'd just be grinding the top part of the socket hole. You won't see it when the bulb is inserted and the lens is on.

 

I had this problem with my FXSTC bucket, to shallow. I bought a new deeper bucket.

 

LED 'bulbs' are a mystery and frustration to me! The darned things don't seem to comply with any of the normal specs for conventional bulbs - in other words too many of them are simply not inter-changeable. As an engineer and shooter I know that the arms industry cracked the challenge of making inter-changeable parts a century and a half ago! So turning down a bl**dy bulb to fit should not be necessary these days, although I must compliment the good Doc for his inventiveness in doing so! Who could possibly have guessed that a lathe would be necessary for such a task in modern times....

After an extensive search I eventually found a pair of bright LEDs to fit our VW T5 van, to replace the daytime front bulbs, in which the LEDs shine back into the reflector instead of flooding light forwards - so they look great and don't dazzle. Result! They also fit the sockets just fine and are much bigger than conventional incandescent bulbs, however the light units are huge, compared with a bike, with plenty of room to take such an over-sized lump.

At the other end of the spectrum I would love a pair of H3 LED bulbs, to replace the stock bulbs in my H-D oval fogs. The light units are bijou, to say the least as also are the stock bulbs, which only just fit. I have yet to find an LED replacement bulb which is anywhere close to the same size. So much for the 'aftermarket'.

I also have a plug-in LED rear light unit similar to what Prot describes, although the entire red cover is part of my replacement. In addition I have an early set of LEDs to replace the indicator bulbs. These are showing their age now and are not very bright by today's standards, so I must seek out a more modern set. So only partial success in converting Hyacinth to LEDs to date.

 

I put one of these in my 03 Sportster and it works fine.

https://www.superbrightleds.com/more...bulb/970/2372/