suzuki hayabusa problem

[itmepop134]

my dad has a T reg Suzuki hayabusa he has always had problems with the battery but most recently once he has charged the battery been out for a ride and turned the bike of it will not start again unless he puts a jump pack on it or wait for it to charge even though when he test the battery it Say's it 75%-100% charge
he has tried to disconnect the alarm this made no difference but has recently had the starter motor changed very frustrating any idea what this could be thanks