charging system

[stuart]

heeeeeelp.....i cant get my xs 1100 to charge properly i have renewed the reg rectifier and cleaned every terminal on the bike it is also a new battery does any body have any ideas?????????????????????????? or maybe where i could get some new generator windings

[skids]

Check the magnetic field at the alternator case cover with a small piece of iron when the key is on. Also, I believe the regulator/rectifier unit has no ground wire connection, but is directly grounded at its mount to the frame. You might clean that contact.

[stuart]

charging system

thanks for the reply buddy....i have been out to my shed and tried this the peice of iron does stick to the casing when the ignition is on.....i am at my wits end with it i may have to put it in to a yamaha dealer soon......$$$$$$$$$$$$$$$$$$$.this i dont want to do.......cheers

[skids]

OK, now that you know the field coil is working, you at least know that the regulator is sending current to try and charge the battery. The next thing you can try is to connect the leads of the multimeter to the auxiliary fuse leads below the fuse box. Run the bike and see what the voltage is across the screws there. You should get a little less than the voltage that the battery is charged to at idle, because the headlight and runner lights normally consumes more than the output of the alternator. Now rev the engine to something like 3500 rpms. At that engine speed, it should show something like 14 volts. If it does, I think your alternator, regulator, and rectumfryer are all fine. You might want to make sure that the battery is still good. I know it is "new" but hey, stranger things have happened. Simply checking the battery after a charge with a volt meter is not going to cut it. You need a load test. A friend of mine said that if you test the battery volts while hitting the starter, you should have well over 9 volts, but I suspect that is a bare minimum!

[stuart]

charging system

cheers buddy i will try this when i have a spare min....thanks

[TonimusMaximus]

I recently tested out my charging system with my multimeter and it brought back a "dead" battery. Here were my test results. Keep in mind these were my numbers, but yours should be close. All numbers are with a disconnected headlight.

Idle: 12.6 V
Idle with brake lights: 12.2 V
2500 RPM: 13.2 V
5000 Rpm: 14.1 V

I never had it go much higher than that. I attached my multimeter directly to the battery terminals to see what the battery was getting. I did test just the batter with the bike off and it had 10.8 V, so I knew everything higher than that was what the bike was putting out. I hope this helps.