LED main, pilot & stop/tail light upgrade.

Lovel · May 16, 2023

marshg246 said:
Did quite a bit of testing today - here's the good:
1) The bulb works correctly both high an low beam with positive ground.
2) The bulb works correctly both high an low beam with negative ground.
3) It works properly with a standard incandescent warning lamp trying both polarities.
4) It works properly with a LED warning lamp trying both polarities.

Here's the only two bad things. The base is about 1/16-3/32" larger diameter which made it harder to get in one beam unit tried and no harder in another. Also, the base length it about 1/4" longer than the H4 Halogen bulbs I removed. In both cases they work fine - just a little extra fiddling.

I fitted one of those headlamp LED’s which works and fits fine, but at idle and slightly above I get a strobe effect. Perhaps something to do with my original fitment rectifier and zenor diodes, in fact I fitted LED’s also to the tailight and instruments and they all strobe in unison now unless I increase the engine revs. Hopefully not going down a rabbit hole here and have to upgrade my whole system ?

hhh · May 16, 2023

Lovel said:
I fitted one of those headlamp LED’s which works and fits fine, but at idle and slightly above I get a strobe effect. Perhaps something to do with my original fitment rectifier and zenor diodes, in fact I fitted LED’s also to the tailight and instruments and they all strobe in unison now unless I increase the engine revs. Hopefully not going down a rabbit hole here and have to upgrade my whole system ?

I think your battery might be struggling to charge to a reasonable voltage, so your system voltage is following your alternator ripple. How old is your battery? LED headlights are more tolerant to voltage range but they have no persistence like an incandescent so they'll strobe under high ripple conditions.

Lovel · May 16, 2023

hhh said:
I think your battery might be struggling to charge to a reasonable voltage, so your system voltage is following your alternator ripple. How old is your battery? LED headlights are more tolerant to voltage range but they have no persistence like an incandescent so they'll strobe under high ripple conditions.

New battery this year, usually on a trickle charge when not in use.

hhh · May 16, 2023

Lovel said:
New battery this year, usually on a trickle charge when not in use.

I'd check it or swap it temporarily regardless. I have had batteries fail in under a year.

Lovel · May 16, 2023

hhh said:
I'd check it or swap it temporarily regardless. I have had batteries fail in under a year.

Took a few voltage readings: looks quite normal to me.
No daylight running lights fitted, UK model, points ignition.

12.60v ignition off, reading from accessory plug
12.00v ignition switch position 1
13.01v engine running at 1,500rpm
12.84 v engine running at 1,500rpm, ignition switch position 2 headlamp on.

hhh · May 16, 2023

The 12.00V with the ignition on slightly suspect. I would expect higher than that for more than a few minutes if the battery is good even with a set of points closed.

marshg246 · May 16, 2023

hhh said:
I'd check it or swap it temporarily regardless. I have had batteries fail in under a year.

I agree. Also, you may have a partly failed bridge rectifier which is allowing AC current in the circuit. With a good regulator and battery, there very little ripple in the system. Finally, if you have the bulbs this thread is about you're the first I've heard of with a problem. If you got the bulbs that have been available for about two years - they have many such problems. Did they come in a red Lucas Box?

Lovel · May 17, 2023

marshg246 said:
I agree. Also, you may have a partly failed bridge rectifier which is allowing AC current in the circuit. With a good regulator and battery, there very little ripple in the system. Finally, if you have the bulbs this thread is about you're the first I've heard of with a problem. If you got the bulbs that have been available for about two years - they have many such problems. Did they come in a red Lucas Box?

I think will try one of those solid state rectifiers first as they are relatively inexpensive. I purchased the bulb you recommended as the Lucas version is not available for my type of headlamp at the moment

marshg246 · May 17, 2023

Lovel said:
I think will try one of those solid state rectifiers first as they are relatively inexpensive. I purchased the bulb you recommended as the Lucas version is not available for my type of headlamp at the moment

Does it happen on high beam, low beam, or both? I tested that bulb as stated but the other bulbs in the bike were standard bulbs and the bike has a Tri-Spark MOSFET regulator and a brand-new hand-made wiring harness.

You could disconnect the Brown/Blue wire(s) from your rectifier and try it. That will remove the charging circuit from the bike so you want the battery fully charged first.

Lovel · May 17, 2023

marshg246 said:
Does it happen on high beam, low beam, or both? I tested that bulb as stated but the other bulbs in the bike were standard bulbs and the bike has a Tri-Spark MOSFET regulator and a brand-new hand-made wiring harness.

You could disconnect the Brown/Blue wire(s) from your rectifier and try it. That will remove the charging circuit from the bike so you want the battery fully charged first.

Removed brown/blue wires and ran engine, still strobing on low and high beam.
Also removed wires to zenors and ran engine, strobing continued. Refitted all connections back. Same.

I don’t suppose I’m getting idle vibration effect on the lamp mixed up with strobing?

marshg246 · May 17, 2023

Lovel said:
Removed brown/blue wires and ran engine, still strobing on low and high beam.
Also removed wires to zenors and ran engine, strobing continued. Refitted all connections back. Same.

I don’t suppose I’m getting idle vibration effect on the lamp mixed up with strobing?

Might be. Wait until near dark, point the headlight at a wall and start it up - look only at the wall. Is the light actually turning on and off or is it moving side-to-side or up and down?