Lexter
XS400 New Member
Hello,
New member here, I just got a 1979 XS400F and love it but (no surprise) the charging system is not working. I have done all the resistance tests according to the Haynes manual and everything passed. The stator does magnetize when I start up the bike. Battery is new and in good condition. Cleaned all the grounds.
I did an AC volt test on the three white stator wires. I read abut two different ways to do this test. The first way I tested each white wire with one Meter lead on the wire and the other to ground. Got a very low reading this way. The other method I used was to test the white wires in pairs (one meter lead on one white wire and the other on the second white wire.) Doing it this way I got about 25 AC volts at 2000 RPM for each pair. Is this good?
The main thing that is confusing me is that when I test the volts at the battery with the rpm's at 2000 or higher the volts do rise but very slowly. I actually held the rpm's at 4000 for about a minute and got the volts up to 13.5 and I'm pretty sure it would have kept going but I didn't want to keep revving the motor like that. I did the VR bypass test and the stator did magnetize but the voltage did the same thing - only crept up very slowly.
Wondering if anyone has any insight into what my problem might be given the slow voltage increase? Or what other tests I could do before pulling what's left of my hair out and blindly throwing money at a new VR, rectifier and stator. Thanks!
New member here, I just got a 1979 XS400F and love it but (no surprise) the charging system is not working. I have done all the resistance tests according to the Haynes manual and everything passed. The stator does magnetize when I start up the bike. Battery is new and in good condition. Cleaned all the grounds.
I did an AC volt test on the three white stator wires. I read abut two different ways to do this test. The first way I tested each white wire with one Meter lead on the wire and the other to ground. Got a very low reading this way. The other method I used was to test the white wires in pairs (one meter lead on one white wire and the other on the second white wire.) Doing it this way I got about 25 AC volts at 2000 RPM for each pair. Is this good?
The main thing that is confusing me is that when I test the volts at the battery with the rpm's at 2000 or higher the volts do rise but very slowly. I actually held the rpm's at 4000 for about a minute and got the volts up to 13.5 and I'm pretty sure it would have kept going but I didn't want to keep revving the motor like that. I did the VR bypass test and the stator did magnetize but the voltage did the same thing - only crept up very slowly.
Wondering if anyone has any insight into what my problem might be given the slow voltage increase? Or what other tests I could do before pulling what's left of my hair out and blindly throwing money at a new VR, rectifier and stator. Thanks!