On our workshop day SSD decided to change his headlight globe over to LED adjustable with heat sink no fan. After changing out the globe they found that they only had one beam. Changing from high to low and even hitting the flasher they still only had one beam. As the globes came as a pair they tried the second globe and they had the same results. Going back to the standard globe fixed the problem. I gave them my spare LED globe, adjustable, heat sink with fan and it had the same problem, one beam. Matt and Gary the Greater ( both Sparkies) checked the wiring and found no problems, it has been fitted with relays. Refitting the OEM globe fixed the problem every time. I didn't have much time yesterday but had a quick look before SSD took off home. I could not find any problems with the set up. This morning I decided to check my spare globe out. Due to the brightness I put on my auto dimming welding helmet and found that the high beam LED was not working. The globe was not running through the headlight wiring but connected to jumper wire setup connected to the accessory outlet for testing purpose. The only theory at this stage is that the globes are faulty which makes 3 faulty globes from two different manufacturers. My spare globe has been sitting in its box for around 4 years and has never been connected to any power. I've told SSD to take the globes back to the supplier and get a refund or new globes. I can't see that anything done during the fitting process would cause them to fail.
Regards Martin.

My 2C is in the other thread . AFAICS, you've pretty well proved that the bulbs are faulty. Apart from duff headlight bulbs, I've also had bad LED stop/tail bulbs where it was very difficult to distinguish between brakelight on or off. I remain convinced that aftermarket replacement LED-type bulbs are not yet ready for prime time. OEM LED kit is a different kettle of expensive fish.

I think your saying flash to pass turns on the low beam, butt it should include the high, so I think that's in line with what Dai says. Maybe high is connected to low. 

Dunno zilch about LED, so here's a high amount of low credibility guessing. 

Is SSD's brick an early model with the different wiring? Is the special equipment plug in the relay box being used?

I'm wondering if the globe needs power to high and low before the high beam comes on. 

Something that would be easier to check than imagine, this sort of reminds me of a relay problem. Changeover type, faulty or where the two pins are swapped around on the modern relays, compared to the ones used on early bricks.

Bad bulbs is my guess.

The high and low beams are different circuits with different beam patterns. There should be no need to activate both circuits to get a high beam.

I've had no problems running LED H4 bulbs in any of my K bikes for the last couple of years. Plug-n-play.

The LED bulbs work much better than any halogen bulbs. (Even in the crappy K75S headlight.)

LED vs. stock halogen:

Low beam:



High beam:

First thing comes to mind is are the diodes polarized?  If so, where is the ground connection?  It would be typical of the ChiComs to use polarized LED's to keep costs down.

Being familiar with ChiCom reverse engineering, I wouldn't be surprised that your LED globes have the ground in the wrong place.  Have you tried different polarity and terminal combinations?

Point-Seven-five wrote:First thing comes to mind is are the diodes polarized?  If so, where is the ground connection?  It would be typical of the ChiComs to use polarized LED's to keep costs down.

Being familiar with ChiCom reverse engineering, I wouldn't be surprised that your LED globes have the ground in the wrong place.  Have you tried different polarity and terminal combinations?

LED stands for Light Emitting DIODE (a diode is a "one-way" electrical component) so LEDs are naturally polarized and even the Chinese, who have been manufacturing LEDs and all sorts of electronics for decades, understand the basic concept of polarity.

Light emitting DIODE.  Wow! I learn something new every day! 

I would hope the ChiComs would know, but I have seen enough of their attempts at reverse engineering to know that the chances of having the terminals wired correctly can be a bit of a crap shoot.  It is also possible that the globe could be designed to be non-polarized. 

And I've dealt with enough orientals to know that when they do screw up they'll often just shrug and say "maybe no one will notice".

...Hey, the low beam worked...

Thanks fellas I'm pretty well set on the globes/bulbs are faulty or possible Alien interference. Maybe we need to wear tin foil hats when fitting LED globes. What is a bit perplexing is getting 3 faulty globes/bulbs in a row. I'm waiting to see what happens when he returns them to the supplier.
Regards Martin.

Charlie the adjustment is so that by slightly rotating globe you can adjust the pattern. The globes are blade type with two LED's per side the low LED has a small shield and is lit all the time. Switching to high beam activates the high beam LED in addition to the low LED. No additional wires are required it is a straight swap for the OEM globe. The piccies are of my spare which is the same as SSD's minus the fan.
Regards Martin.

ah ! 
by adjustable , meaning globe position ...makes far more sense,   thanks for the clarification Martin.




would just like to add 

leds blow up verry easily at the slightest hint of reversed current flow 

yes they can take 35-50 volts in the forward direction  but even 6 volts in the reverse direction will cark them before you could blink 


they will not survive experimental testing at all.

 i have found those types of circular illumination , and dual on status leds that don't have a clear cutoff whilst on low beam are a frigging bane to every on-coming traveler , in fact i have 1 in the car that always has irked me , and still get flashes from vehicles travelling in the opposite direction periodically, i also have a few local riders with similar , without an off switch available , meaning whilst riding the headlight is always on  and whilst this is ok if they are in front a real pain if they are behind almost as bad as hid in incorrectly designed reflectors  or retrofitted to standard headlamps .... my little problem child will be rectified pretty soon .... luckily i don't travel far or often at night these days.

charlie99 wrote:"headlight globe over to LED adjustable"


why would you want led adjustable headlights 


either on high or on low would suffice  as there is no dimmer option available at the controls 


i would recon that these globes might require a 3rd active wire to adjust the brightness  and as our switches only have either-or ...wouldnt be able to control the brightness






perhaps a link to the actual supplier and model of the globe would reveal more information 

Adjustable does not mean dimmable. Some of the "adjustable" LED headlight bulbs will ROTATE so you can have the beam hit the sweet spot of the reflector.   I have LED bulbs in a car and a half dozen K bikes. A properly made H4 LED bulb requires no adjustment. As you can see in my images above both high and low beam patterns for the K are right where they should be with no scatter.

Back in the mid-teens when LED headlights first came out they were crap that just put out tons of light in no particular focused direction. By the late teens you could get decent LED headlights with good brightness and beam patterns but they weren't cheap.  BY 2020 the ChiComs were producing consistently good LED headlights at reasonable prices. After I upgraded my car with LEDs with good results I moved on to finding good ones for Ks.

Charlie I didn't come into the equation until the party was over. However I can't see how they could have reversed the polarity it was pretty much fit the globe and plug it in. I'm trying to get more info off the Salty Sea Dog.
Regards Martin.

had the same experiences here Duck 
after trying the high power halogen options .


ive got a handle on a few good to use designed  and reasonably priced h4 globes that i would recommend if leds are a thing that they would like to do.

something like this 
 .

MartinW wrote:Charlie I didn't come into the equation until the party was over. However I can't see how they could have reversed the polarity it was pretty much fit the globe and plug it in. I'm trying to get more info off the Salty Sea Dog.
Regards Martin.

yes got that Martin .

hmm did you mention that the owner had implemented  relay options 

i wonder if there is a switching issue where the high beam relay wiring is interacting with the low beam . 

perhaps measuring with an incandescent globe installed  both high and low beam terminals in respect to an actual good earth point  could reveal an issue ?
 like the high beam indicator lamp in the instruments being installed backwards ?  or something like that ?

just trying to help solve the issue , all 3 leds couldnt have been defective , surely ..

Charlie I found out what brand globes were used and on the vendors site they have a one star rating out of a possible five. They seem to be renowned for failing. According to the specifications the LED's apparently also have incorrect polarity protection. And if there was something screwy with the wiring why didn't it stuff up the OEM globe and blow the low beam LED. I'll get him to bring the bike over and do some more testing unfortunately it was a bit soggy today.
Regards Martin.

Martin wrote:  "According to the specifications the LED's apparently also have incorrect polarity protection."

That was my thinking.  It wouldn't be the first time a ChiCom engineer got terminal assignments and polarity azz backwards, and sure as heck it won't be the last.   

I could see them wired such that instead of switching the positive voltage to the hi and lo beams, the ground is switched, or the beams are in series instead of parallel.  Who knows how it was designed?    I suspected that to make them work you would have to rewire the headlight connector and possibly the switching.

Recently a new stator and regulator (chinese) needed to be replaced   every thing was fine except the output from the regulator was wired to the connector exactly reverse  , at engine run mode and the engine actually starting it blew the protection fuse and realy caused a battery ( also new) to have a hernia   of sorts   .....gotta love their qa...  eh ? !!!

From the workshop thread Martin writes "My 75 fitted with the same LED globe has normal Hi/Lo operations"

That's the bit that made me think, seems like the brick, not the bulb. I'm thinking what's the difference between the bricks. I'm thinking does SSD's have the earlier wiring, and I'm guessing Martin's brick doesn't have a headlight relay, If so then that would be another difference.

Dave mine has relays with the identical wiring set up as SSD's. When I fitted SSD's Brick a 91 K100 LT with relays there was an intermittent problem, Matt (Sparky) who was there at the time checked out the wiring and it was fine. He had previously found a problem with the this type of inline fuse holder. A bit of tweaking with the fuse holder fixed the problem. SSD has now decided to stick with the OEM globe.
Regards Martin.