Headlight dimming at high rpms

3 replies to this topic
  • dnthmn87

Posted March 28, 2011 - 10:29 AM


I recently bought a 2003 WR450, and I think might have had a baja designs kit on it at one point, because there is what might be(i know little to nothing about electrical systems) the rectifier that has the baja designs logo on it.
It has an acerbis headlight, new battery, and working brake light.
The problem is that when I rev the motor up the already dim headlight gets dimmer:foul:, but if I hit the rear brake at any rpm, the headlight gets brighter, and the brake light comes on too.
As of now there are no signals, or horn on the bike, just an on/off switch for the headlight on the handlebars, and a high/low beam toggle switch on the side of the headlight.

  • William1

Posted March 28, 2011 - 10:55 AM


Sounds like a bad ground. Time to unplug and inspect every connection.

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  • Brawg

Posted March 29, 2011 - 12:23 AM


voltage regulator?

  • gsa102

Posted March 29, 2011 - 08:33 AM


+1 bad ground.

When you activate the brake light you are providing another ground path for the headlight, which lets more power through the headlight filament, making it brighter.

Had the same thing on an old jeep's headlights, makes weird stuff happen.


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