AJS & Matchless Owners Club

Hi hope someone can help the dynamo on my G80s stops charging after the bike has been left for a week or so have to clean one off the brushes and away it goes again have changed both brushes and it still doing it the brushes are free and the brush spring are good can not find the answer to this.

Are the brushes too soft? If you can write with them on paper they're no good.
Dave.