They will often need more than a soft cloth, if it has been stood a while it might need a bit of 1000 paper while it's running.
Dynamos can be strange beasts, the one on my twin never needs touching whereas the one on my Brough needs the commutator doing every few hundred miles.
Dynamos can be strange beasts, the one on my twin never needs touching whereas the one on my Brough needs the commutator doing every few hundred miles.