Of course taking the grinder to the stator wires clipped them. Now I need to solder on new extensions for 2 of them. At least the brushes are in and desoldered. A little tricky onto the thick meta that's hard to get hot enough.
Hopefully I have the 3 wires back in the same order if it makes any difference. I was going to go for a test ride but realized I didn't have a helmet there so hopefully Sunday I can do a test ride.
Yay! I think I got it! I finally got out for a test run today and when I got back the battery was charged just fine, not like before when it would run down after a bit of riding. Feels good!
Hopefully I have the 3 wires back in the same order if it makes any difference.
No, none at all. The alternator has a 3-phase AC output, which the rectifier board changes to single-phase DC. So it makes absolutely no difference.
Owning an old Airhead is easy.
Keeping an old Airhead running great is the true test.
Yay! I think I got it! I finally got out for a test run today and when I got back the battery was charged just fine, not like before when it would run down after a bit of riding. Feels good!
Great news indeed !!
What happens when the brushes get short is that the spring starts to press on the brush CAGE instead of the brush. Like any electrical connection, there must be some pressure (in this case spring pressure) to overcome surface resistance. With no power able to reliably get IN or OUT of the rotor, all the magnetism disappears and the output of the whole alternator stops.
The alternator works because a magnet is spinning inside the stationary coils (the stator) induces electrons to start moving. Cheaper alternators use permanent magnets, but the Airhead is more advanced. It uses an electro-magnet so that the amount of magnetism present in the spinning rotor can be controlled by the voltage regulator. When the battery is low, the VR pumps up the electrical flow into the rotor and the stationary coils output massive amounts of electrical power. When the battery is charged, then the VR reduces the power to the rotor, and thus output to the battery is similarly reduced.
The whole design rests on being able to get electrical power into the spinning rotor to enable this "magnetism" to take place. The brushes are how static (non-moving) wiring connections are made going into the spinning rotor. Poor condition brushes therefore equal poor alternator performance. Its as simple as that.
Owning an old Airhead is easy.
Keeping an old Airhead running great is the true test.
Yeah...simple. Oh yeah, that's me! 😛
Richard's explanation is exactly right. The true test is for Mike B to get a few hundred miles over several test rides to proof out the repair.
former Airmarshal, IL.
Correct, I'll be working to get out on a few rides as soon as I can. It's a bit tough with my current work schedule but I'll give it a go. I know my soldering of the new wires wasn't a great job.
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