[quote author=IdahoDoug link=board=2;threadid=4871;start=msg37769#msg37769 date=1062657785]
As for heat load, I've always been mindful not to have the high beams on while stationary (setting up a tent, for instance) unless it was quite cold outside (lighting up a sledding hill). I've never had any overheat symptom on this or the dozens of prior vehicles I've added upgrade bulbs to. The one exception would be the time I put a 130W bulb in a Hella 3000 Euro Beam and stood in front of it. I literally ran back to the switch because it created a warm circle on my chest a few feet away and I knew it was not long for the world. The bulb (w/ 18 seconds of use) still resides on my shelf.
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Just a point of clarification, the reason to upgrade the harness is (1) to deliver full voltage to the lights so they actually produce the watts indicated on the bulb (without the harness you can be quite sure that the 100W bulb is not producing 100W) and (2) the 'overheating' is generally not an issue of the bulb being too hot (although this can be a problem with plastic lens covers - a few fellow BMW Motorcycle riders have melted tail light lens covers with higher intensity bulbs) - the issue is the connections not being up to the additional load (ie switches, connections, wiring). The thinner wire = more resistance = more heat build-up = overheated components/brittle wires/shorts/etc. The upgraded harnesses have biefier components to reduce this risk, although the stock harness can probably survive (but not address point #1)
You can probably get a sense of the problem by running your high beams for some time (1hr) and then hopping out and checking the temp of the wires running to the light. If I'm not mistaken, if you have a 65W light running at 13V = ~5Amps vs 100W at 13V = 7.7Amps = ~54% increase
Cheers, Hugh
As for heat load, I've always been mindful not to have the high beams on while stationary (setting up a tent, for instance) unless it was quite cold outside (lighting up a sledding hill). I've never had any overheat symptom on this or the dozens of prior vehicles I've added upgrade bulbs to. The one exception would be the time I put a 130W bulb in a Hella 3000 Euro Beam and stood in front of it. I literally ran back to the switch because it created a warm circle on my chest a few feet away and I knew it was not long for the world. The bulb (w/ 18 seconds of use) still resides on my shelf.
[/quote]
Just a point of clarification, the reason to upgrade the harness is (1) to deliver full voltage to the lights so they actually produce the watts indicated on the bulb (without the harness you can be quite sure that the 100W bulb is not producing 100W) and (2) the 'overheating' is generally not an issue of the bulb being too hot (although this can be a problem with plastic lens covers - a few fellow BMW Motorcycle riders have melted tail light lens covers with higher intensity bulbs) - the issue is the connections not being up to the additional load (ie switches, connections, wiring). The thinner wire = more resistance = more heat build-up = overheated components/brittle wires/shorts/etc. The upgraded harnesses have biefier components to reduce this risk, although the stock harness can probably survive (but not address point #1)
You can probably get a sense of the problem by running your high beams for some time (1hr) and then hopping out and checking the temp of the wires running to the light. If I'm not mistaken, if you have a 65W light running at 13V = ~5Amps vs 100W at 13V = 7.7Amps = ~54% increase
Cheers, Hugh