Poohbear's analogy is right on...your bike is essentially a battery system with alternator/regulator setup to surface charge the battery, power the EFI, ECM etc. and any excess voltage is "dumped" by the regulator as excess heat. Wonder what would happen if the battery is not there? You really do not want to find out, as the battery also acts to store and dampen the high voltage transient spikes that the alternator/diodes are putting out, while the alternator tries to put out as much power as possible to compensate for the lack of 250A or more of CCA and reserve power the battery supplies. Without the battery, the stator/regulator parts will overheat, the insulating varnish melts, windings short to ground and turn into cooked spagetti. This is not something you want to have happen...