'84 xt600 electrical issue
 

I'm the brand new owner of a not-so-new bike. I picked up this '84 xt600 with about 7k on it. It's in about the shape you'd expect for a thirty-year-old bike, but it does run and the motor seems strong. The main serious problem I'm facing is an electrical one, and I'm not familiar with how this bike is set up. The issue is this: when I turn the key, the electronics come on: headlights, brakes, signals, horn, but they are all a little dim. With the bike idling, they work fine, but as soon as I rev the engine at all, the headlight dims, the horn won't work, and the signals are barely visible. The battery is only a few months old, if that's relevant.

I can't think why the electronics would operate worse with any revs, but I suppose there's an issue with the stator (?) or the alternator. Do you guys have any thoughts, tips, or recommendations?

Start up bike and measure voltage on batteri, check if there is any difference when rev.

There is a difference. My old multimeter was showing 11v at idle, and it dropped to 9v or 9.5v at rev.

Try another battery, rectifier maybe not doing its job.

From the readings ... suspect is the rectifier/regulator.

I will definitely look at the first and foremost. Is it likely that will have damaged my battery?

Depends on how long the battery has been abused and your luck.
If it is a wet cell then check the fluid level - should at least cover the plates, I'd not bring the level up to more than covering the plates before charging it.

Mate, you need to check your stator..

On the 1990 and up model you need to unplug the white connector that comes out of the engine and check for continuity between all three wires (two at a time) and they need to have continuity!

Second test is to check for continuity between the wires and a good frame ground! It can not have any continuity to ground!

As for the regulator/rectifier it is not as easy to check it unless you know how to do a proper voltage drop test across all pins..

Your particular bike model I am uncertain but the procedure should be the same!

Let us know if you need any help!

Merry Christmas!