Dimming lights

[Brian2]

The last ride I went on with my 1995 KDX200 lasted longer than I had expected, and the return trip was in the dark. Now for the problem: my headlight would get so dim that the only light coming from the filament was just an orange glow, same with the taillight. Unless I turned the lights off for a minute then I could ride with them at full brightness for about another 5-10 minutes. Sometimes the lights would be intermittently orange - then full brightness a few times before fading to orange. I tried tapping things when the lights faded, such as hitting the switch casing, and jiggling the wires to the headlight, but had no luck with that. What's wrong with my bike?

 

[Gladiator]

Most likely you voltage regulator is going bad. It can be tested pretty easily if you have the service manuel and an ohm meter. It may still test good. Your nest option is to beg one off of someone and test your bike with the new one in place of your current one. Maybe a short to ground starting also. Good luck and let us know what it is when you figure it out.

 

[canyncarvr]

Is this an SR? Where are you from? Does your bike have a battery? Or maybe a street kit has been installed? (Some states require a battery to keep a taillight lit for 'x' seconds with the motor off.)

No reason a US dirt bike would act any different lightwise having run the bike for awhile with the lights off.
***edit**
Well, yes there is. If it's a heat related problem...say through a connector or switch.

 

[NHtrailrider]

Sound like you might have some corrosion or a bad connection somewhere in your lighting circuit. Heat will cause resistance resistance too. If you had a problem with your stator or voltage regulator, I think you'd have a problem with your coil also. This doesn't seem to be the case. If you can figure out how to test for "voltage drops", this will tell you where the problem is (ie, switch, connectors, grounds...).

 

[Boot]

I had headlight problems too. I found that one of the wires coming out of the alternator was shorting against the flywheel intermittently. The flywheel had rubbed through the insulation. You might want to check this.

I also seem to have had something funny going on with my headlight switch, but my SR has a full switch block that is probably different to yours. Anyway, I pulled it apart and cleaned it and things got better.

You can also try isolating the tail-light circuit completely to see if you have a short in your rear-end, so to speak.

 

[canyncarvr]

Don't 'isolate' the rear end by unplugging it at the headlight shell area.

You'll also be disconnecting the regulator......and be blowing filaments.

 

[Brian2]

Correction for my description of the problem:

"Unless I turned the lights off for a minute then (BACK ON AGAIN) I could ride with them at full brightness for about another 5-10 minutes."


This is an H1 1995 bike for "The states", no battery, no street kit. I'm in Massachusetts. Thanks for the help, will check the regulator and wires for wear on the insulation.

 

[canyncarvr]

If a wire was shorting to something, the lights would flicker or go out...not likely to dim or glow 'orange'. That's a lot more likely (regulator being ok) to be a resistant connection somewhere, ground OR power.

If possible, feel the connections you can get to to see if any of them are warm. They shouldn't be. If you find one that is, at least reseat the connection. At best, replace the connection with either a good quality crimp or solder a lesser quality crimp connection.

A bad solder job is at least as bad as a poor crimp connection. Too much heat will wick the solder up the wire making it less flexible and therefore more prone to breakage.

Insulate the connection with a piece of heat shrink to keep moisture and crud out.

Any place there is a ground-to-frame connection, take it off, clean it, make sure the frame is clean, put it back together with some anti-oxident grease.

Good luck. Wiring problems can be a pain.