For some time now my generator light is staying on for about 4 miles of riding and then flikkers and goes off,which it would do normally before if you rev it up a bit,right after starting it..IF i ride every day no problem,but if i dont run it for say a week it will take about 4 to 5 miles of riding before it goes off and starts to charge again,if lite is on no charging.Any ideas? Thanks

 

The brushes may be sticking. Here is a thread on inspection and cleaning ...

Ironhead 1977 generator brush inspection (with details and pics)
http://xlforum.net/vbportal/forums/s...d.php?t=589224

That author did this with the gen still installed on the bike. I would not do that; better IMO to work on the bench.

 

Thanks Iron Mick,i cleaned them tonight and looks like the lite goes off with a little revs,i,ll have to let it sit for a few days to see what happens.It was dirty .

 

the magnets are weak - they are not hi quality stuff to begin with - and as you are riding and the currect is increasing the magnets get rejuvenated finally the field goes totally to ground and the light goes off

as it sits the magnets loose the charge and need voltage to bring them back --

 

Hey John, magnets in a generator? Perhaps you are thinking of an alternator

 

The field circuit consists of two coils of wire wound around iron poll shoes. The poll shoes are mounted opposed each other on the inside of the generator housing. One end of the coils connects to the A terminal and the other end connects to the F terminal on the generator. The armature is mounted on bearings and held between the poll shoes. When the generator is first built it needs to be polarized. This is done by flowing current through the field coils. This current makes a magnetic field and magnetizes the poll shoes. One shoe will have its north poll facing the armature; the other poll shoes south poll will face the armature. The polarity of the poll shoes will determine the polarity of the out put voltage at the A terminal. When polarizing it is important the make the A terminal more positive than the F terminal. Flowing current the other direction will make the A terminal have a negative voltage.

 

I get that, but there are no magnets in a generator like there are in an alternator?

 

This current makes a magnetic field and magnetizes the poll shoes -


is it not than a magnet -

we are talking about the windings ( pole shoes ) bolted to the generator housing with big screws