2004 wr450f electrical problem

Hey guys,

I got my '04 wr 450 f about two weeks ago. Mechanically the bike is great. Starts easy, runs smooth. The only issue is the guy I bought it from put a light kit on it to make it street legal. Everything works except the headlight. If I turn on the ignition all turn signals and the horn work but the headlight will not come on until I crank the bike. The headlight also does not switch from high-beam to low-beam. Also my brake light only brightens up when I press the foot brake. Being a mechanical engineer I know just enough about electricity to get myself in trouble. Any suggestions or thoughts on what may be causing this?

O.k.. sounds simple enough.. The headlight(55w)if still stock Yamaha, will never work on that bike without it running..as the other items are using your 12v battery supply.. unless the headlight is not stock had LED bulb but that's another issue..

Also the reason if it is a stock headlight the unit never had a hi/lo beam so it tied only to the main light power from the engine power supply..

So you could find a electrician whom would wire in a resister to make the low beam half as bright as the hi beam.. but it would never project as much of a difference as a real hi/lo beam system.. This is where a actual head light that has the correct function work.

The brake light is also a easy fix.. There must be a pressure switch/banjo bolt on the front brake master cylinder hose(there was one installed on the rear brake or a spring /pull activated one).. if there is not one on top or at the caliper then that's the problem.. one needs to be there and the aftermarket harness installed has the provisions. If there is one , maybe the wires pulled out of the harness.. or the pressure switch is bad(they do go bad)..

Hope it helps but if unclear give me a yell and we can talk it out.. Carl 570-527-6849

Thanks man that seems easy enough. It is a stock headlight which isn't very bright so I'm going to look into upgrading it. Any suggestions on brand/type?

The stock WR headlight has the capability to be a hi/lo set up it just needs a hi/lo switch. If you already have a switch it may not be wired correctly.

Edited by SPLATT

I already have the switch. Ill research more on the wiring to see if it's possible/how to do it and post an update if I find anything!

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