Higher Wattage Headlight = Problem

[Roadie]

Last week I replaced the stock 55W low beam bulb with a 100W H1 bulb without any problems. Yesterday I did the same thing with the high beam and lost the low beam. The high works with the new bulb but the low doesn't work with either the 100W or the original 55W.

The manual doesn't list any fuses for the headlights but that doesn't seem right to me. Does anyone have an idea of what's wrong?

TIA, :dunno

Peter

[jdiaz]

The stock wiring goes from the battery to the left grip switch then out to the headlight(s) without fuses or relays, and the wiring is THIN. Since both lights are left on in the high beam position, you may have melted your low beam headlamp connector.

[Roadie]

Ouch! Maybe I got greedy trying to use the two 100W bulbs. Thanks for the tip Jon, I'll check this out with my local BMW wizard.

Peter

[cat0020]

I run a single bulb with 110/100w dual filment on my R1150RS, with 6500 miles so far without a problem.

Originally posted by Roadie
Ouch! Maybe I got greedy trying to use the two 100W bulbs. Thanks for the tip Jon, I'll check this out with my local BMW wizard.

Peter

[Roadie]

cat0020:
With the single bulb you're probably not putting the strain on the switch that I was with two 100W bulbs. I think I've cooked the low beam switch – now I have to figure out how to fix that. If anyone has any suggestions let me know.

Peter :confused:

[lorazepam]

If you can get the switch apart, you might be able to use an emery board to clean the contacts, but I suspect that you have probably melted it. See if you can get the switch from a slavage yard, they are very helpful in locating parts online for a lot less than you would pay a dealer.

[Roadie]

Indeed there is a fuse for the low beam! #10 fuse 7.5A. Not listed in the manual but that's the one that was blown.
Problem fixed! :)

[bertbrumfield]

i WOULD NOT RECOMMEND RUNNING 100 WATT BULBS ON THE STOCK WIRING. it will work for a while but will not carry the load for long (it will get hot enough to melt the plastic off the wires). DAMHIK. I ran 12 gauge hot and ground wires from the battery to a 30 amp relay and used the stock wiring to control the relays. the 12 gauge wire will easily handle the 2 100 watt bulbs. be careful of the ground wires and do not use the stock wire from the relay to the bulbs, either.

[Roadie]

Thanks for that info. I will follow it and get those 100W bulbs back in when I'm done with that wiring! :bliss