A fuse has a finite life, meaning that the more it is used the weaker it becomes. Therefore although the ignition fuse is designed to blow at 30Amp that includes a safety factor, theactual ignition current is probably very much less. Eventually the value at which the fuse blows will fall to that of the ignition current, at which point the fuse blows. Don't worry unless the ignition fuse keeps blowing, then you have a problem. This problem is usually water ingress, or damage to wiring insulation, recently I managed to get water into the fuse box, this caused the ignition fuse to blow when leant over on roundabouts. Not a particularly safe place for the bike to coast to a halt!
|