Motorcycle charging problems can reside in a faulty stator not generating (enough or any) electricity. The stator is the fixed part of the alternator around which the magnetic flywheel rotates generating AC power that is then passed down to the regulator/rectifier, which converts it to DC power ensuring the voltage is within certain limits not to damage the battery. Faulty stators can be a more common issue on larger engine/more powerful motorcycles that generate large amounts of AC power basically frying the stator.
Replacing the stator is not too complicated and requires a socket set and some heat resistant gasket repair silicone only. As a guide you can expect to pay about £80 for a new stator on larger engine motorcycles and about £5 for the gasket repair seal. The photo shows a 2007 Honda CBR1000RR Fireblade, which model (06-07) is highly affected by this problem therefore Honda extended its manufacturer warranty from 2 to 7 years for VIN numbers within a certain range, but other manufacturer's models can also suffer the same issue. If out of warranty (as this example) the manufacturer will probably (Honda UK certainly) refuse to help even just by supplying the defective part for the problem they are very well aware of. It's still worth a try, but if you rely on your motorcycle running as soon as possible, you are better off fixing it as chances are you'll end up doing it regardless. On 2006-07 Honda Fireblades the stator is located on the left hand side behind the crash protector.
*Step #8 is the hardest and most sensitive part as nothing to grab onto and the gasket seal and magnetic flywheel holds the cover in place. Try tapping the cover around gently to break the seal, but note that the gasket cover cannot slide off sideways as there are pins inside holding in its designated location. Sometimes its helpful to wedge a thin piece of plastic/wood (do not use metal as it can easily damage the body or cover) into the gap when it starts coming off as the gap tends to close immediately when the cover is pulled from the opposite side as the strong magnetic flywheel pulls the cover back into place.