By "no fire" do you mean that the magneto is not producing a spark? I agree with the comment that this could be points. The contacts can become oxidized if they sit a while. You might try passing a dollar bill between the points while holding them closed.
Could also be your coil is bad, or a loose connection, or the condenser, Or the cap, or rotor.
or the impulse spring might be broken. Does the mag give a good snap as you turn it? If you don"t hear that snap, then the mag is not turning fast enough to generate a spark as you are trying to start it.
Anyway, I would start with the points if it is not making a spark.