Hey after doing my f4i conversion I put 2 55w halogen bulbs in my headlights and they ran fine for about 3 mins before they burnt out. The cause MIGHT be because I touched the bulbs but is there anything I should check before I potentially waste another 20 bucks in bulbs?

This is on my 95 f3, and I am using a double throw relay for both headlights at once. Thanks

 

I would measure the voltage of the wires leading to the bulbs just to make sure your not over powering the bulbs.

Did you also upgrade the ground wires for the headlights?

If you touched the glass portion of the bulb, that could be the reason they blew. The oil from your fingers will create hot spots as the oil heats up on the glass and can cause it blow out. It usually just limits the life of the bulb, but if your hands were dirty, it can cause them to blow out pretty fast.

is your relay rated high enough for the draw for both bulbs? Sometimes not enough power can be just as bad as too much.

 

I did not upgrade the ground wires, I just ran some 16g wire back from each bulb to the ground post on the relay. I wore some nitrile gloves when putting th new ones in, we will see what happens tonight

 

Yup, burnt out another pair of bulbs. They did seem to brighten before burning out rather than dimming. I measured about 12.75volts across the wires with the bike not running. Ill check the voltage while running once Im off work here in a hour or so.

I assume that the relay that I bought from Orileys can handle 2 55w bulbs. I dont know where to go from here.

 

It seems like you might have something wired up incorrectly. what are the specs on the relay you have?

Also, do you have the high beam side running through the same relay as the low beam? I would only run one relay for the low beam. Have it triggered by an ignition hot source so it stays on all the time. Then you can simply use your high beam switch wires to activate the high beam so both will be on with the high beam. As long as we are talking about the split F4i headlights with two 55 watt bulbs, one is a low beam and the other is a high beam.

 

Ok so I checked the running voltage coming straight from the battery to the headlights and its around 14.6volts. Is this too much and is this whats causing them the burn out?

I also bought a new relay, 4 pin rather than 5

 

14.6 should be fine. I believe most headlight bulbs are rated to up to 16 volts. A common improvement for headlights is to add relays so you get direct high voltage battery voltage to improve the brightness of the headlights. Most of those kits get the volts into the mid 14 volt range.

What does the voltage go to when you bring the rpms up to 4,000? If its higher, you may have an issue with your rectifier.

I really have no idea why your headlights are burning out. If it was an over charging issue, your other lights should also burn out too, not just the headlights.

Can you draw a quick wire schematic of how you have everything wired up? show the hot and ground wires, relay, headlight bulbs pos, neg. and type. I still think there is something wrong with the way its wired up.

also, you are only running one for low and one for high correct?

 

Ok here is my atempt at a schematic. In case you cant read my relay key it is 1-switch 2-throw(1) 3-throw (2) 4-Power from battery 5-Ground

I also have a 30amp fuse coming off the battery.

Keep in mind that this is a f3 to f4i swap so I used the high beam line as my switch.

 

Im not sure why you have the high and low beam from the headlight acting as the switch wire. I think with you having them wired together, you are getting feedback into the non powered side. Basically, your powering the high beam side of the harness when its not suppose to be powered when you have the low beam activated, and vice versa. That very well may be the issue right there. Also, the ground from the headlight harness is not a good enough ground for the relay. If you are powering direct power from the battery to relay, you also need to supply battery ground as well.

I drew up a quick schematic in paint of how I would wire it up. I used the same number system that you did, so refer back to your drawing for what each number is. But basically, the low beam side of the headlight is not used, and neither is one of the power outputs.

Also, I noticed you are powering both headlights at the same time. Is there a reason you do not want a functioning high beam?

here it is. I think it should be fairly easy to follow.

 

Thanks for the reply. I may have drawn that part incorrectly, I just have the high beam acting as the switch for the relay. The low beam wire is not used.

In regards to your setup my question is why? You have it set up as if i was only using a single pole, single throw relay, I have a single pole double throw, this way I can control both lights with one switch.