Testing the headlight on my '85 ATC250R

[Qdude79]

Fresh off a nut and bolt rebuild, my trike had the wiring for headlight when I bought it, but no headlight (or taillight, for that matter). Have since added a headlight with a brand new bulb but don't get so much as a flicker. I'm a novice with a multi-meter, but I have one, and get low AC voltage readings (single digits) when it's running. Can anyone give me some steps on how to diagnose my problem?

[Qdude79]

63 views over two days and nobody knows???

[Mr. Clean]

http://www.oscarmayer.net/atc/manuals/

Download the Honda 250r Manual. It gives you all the information you need to test the headlight circuit.

[Qdude79]

I've got it and tried it. Does not tell me what I should be getting out of the headlight plug. Just how to test the lighting circuit for connectivity.

[Qdude79]

Anybody willing to try and get readings from their working headlight plug that I could compare to so I at least know what it SHOULD be?

[Varget22]

Make sure you have your meter set to read AC and not DC. It should be in the neighborhood of 12 to 14 volts AC depending on the rpms of the motor.

[Qdude79]

Thanks Varget!

I did that, (making sure it was AC) and all I got was somewhere between 1.5 to maybe 4 volts when revved. Bike runs fine otherwise. What would that indicate? Lighting coil? Alternator altogether?

Thanks again, now I feel like I'm getting somewhere!

[Varget22]

Measure the amount of AC voltage going into the regulator from the generator. According to the schematic it is a yellow wire with a white stripe. I'm not exactly sure what the amount of AC voltage is but it should be a good bit more than 14 volts.

[Qdude79]

I will do just that. Thanks for the direction! Might be able to get to it this evening if I get home in time to fire it off before the neighbors try to hang me by my toenails...

[oscarmayer]

did you turn the light switch on? was the motor running?
sorry but I seriously have seen some interesting responds to those 2 questions lately when asked about the same exact thing.

the best was " motor is not running"
DUUUHHHH it wont show a light w/o the motor running. it has no battery!!!

I'm sure your smarter than that. but had to ask anyway. as mentioned. check that voltage at that point, then check coming out of the stator area itself. if also low, then yes bad lighting coil. if hi coming out of stator area but low out of regulator, then bad regulator.
hope this helps.

[Qdude79]

Will do, Oscar, and thanks!

Yes, engine running. That was the "neighbors trying to hang me by my toenails" part. Checked switch, good there. Will be testing voltage from stator and regulator, repsectively.

[Qdude79]

Took voltage going into the regulator (yellow/white wire) and barely got a reading (.1-.2 volts). Throw a few revs into it and might get above 1 volt, maybe 1.5. These are the same readings I was getting at the headlight plug.

Thoughts?

Also, I'm not understanding how this system works. Is the voltage regulator only for the lighting? The bike runs without it. Also, how DOES it run with such low voltage output, or is that just the lighting circuit? Fires and runs just fine.

[Qdude79]

Anyone? I'd like to take this thang out this weekend.

[Qdude79]

Ok, so assuming it's a bad lighting coil, what do I need to do to replace it? As best I can tell it's not a single part, but I'll have to replace the whole alternator. Correct?

[barnett468]

Ok, so assuming it's a bad lighting coil, what do I need to do to replace it? As best I can tell it's not a single part, but I'll have to replace the whole alternator. Correct?

ok, heres another test and this is summary of how the manual states to do it.

Remove the gas tank

There will be two separate wires with bullet connectors and two wires going to a two gang plug . . the lighting and spark coil are the two bullet connectors.

Unplug yellow/white wire.

Set ohm meter to lowest setting.

Connect one end of meter to the end of the yellow/white wire that goes to the stator.

Connect the other end to ground.

It should read from .1 ohms to 1.0 ohms if it is good . . post results when done.

pulser = 2 wire plug

exciter coil = black/red

lighting coil = white/yellow . . should be .1 to 1.0 ohms

if you need a new lighting coil you need to buy the whole stator . . yes that sucks.

Here ya go . . $150.00

http://www.rickystator.com/product/s...t-stator-85-86


they can also rewind yours but you can also rewind your own if you know how.

http://www.rickystator.com/page/rewinds