Electrical Issue
 

Hey guys n gals, I have what may be an odd question regarding the lighting system.

I am in the process of getting my xt back to street legal condition, and have noticed something kinda odd.

When I hit the brake lever (hand or foot) the headlight will brighten up for a second them go back to "normal". (normal doesnt seem that bright for the headlight either)

I have no turn signals on my bike yet, I have an aftermarket ignition, I have no battery installed yet, the kickstand switch has been disabled, and other then that stuff, the bike is stock, as far as I know. ( I do have a 1988 year motor installed, but it was doing it with the original engine too)

I have yet to start going through the wiring harness, but the harness looks good, and clean(I will be going through all the connections and double checking them yet though)

My tail light also doesnt come on when the bike is running, but the brake light works as normal (will the tail light come on when the bike is running, when I have a battery installed?)

Anyone have any ideas why my bike may be doing this? Will this smarten up when I get a battery and signals installed?

I'm no auto electrician, but things like this are usually down to a broken or poor earth somewhere.

I think you're going to have to check the lighting circuit methodically for breaks or bad connections.

hey there! you sure it's a 88 motor?

If you have an E-model (the other engine being After 1989 I can see a problem there with the wiring harness)

88 should be CDI and the 1990+ are TCI....

also... the rear "presence" light check the bulb! It's not unusual for the rear brake bulb to loose one of the filaments...




Vando :cool4:

I think Ted's right on the money here. What's happening is that the earth for the headlight is not adequate. When you put on the brake light it provides an additional earth path for the current through the headlight bulb circuit, so the bulb brightens slightly. I suggest you clean every earth connection you can find that any of the lights use and then get the battery back in so that you are using a constant voltage to test things with. Try it with the engine not running and see how it is.

Geoff

Thanks for the replies fella's. Will be checking all the grounds and cleaning them as soon as it gets nicer out again.

As for the year of the engine, Im pretty sure it was a 88, might have been a 89 (will get the numbers off of it if the rain stops tonight to verify) but it is the kickstart only model, and it bolted right in place of my original 1985 engine.

It is usually a good idea to run a clean earth from the handle bars and headlight unit back to the battery. If there isn't the current will flow through your steering head bearings making them appear and feel like they are pitted and worn out. The pitting is actually the results of arcing.
This is especially true when the horn circuit is grounded to the handle bar to work.