Look actually I do not know this motorcycle but for what you say
the reason for the click of the cylinder is in sight, without oil pump the friction produces the grip on the motorcycle and in any machine in general, so I would advise you that
before buying it you fix yourself in the grip, if the piston stuck, if it has material scratched in the shirt and in general if there are vestiges of the piston between the piston. Shirt, if they exist, think that you should check or change shirt, hoops and piston just to start, I hope I have helped you. A cordial greeting from Ahoniken 10