I have just got back from using our bike because a problem has just occured. The bike is having problems shifting into gears, it will change occasionaly but something isn't right! Also, when you release the clutch in neutral I can hear a rumbling noise coming from the gearbox or possibly clutch, when you pull the clutch in the noise goes away. My mate has sometimes had problems in the past shifting into third so maybe it is a problem that has slowly gotten worse? What do you think is up with it? I thought maybe the clutch is knackered but I am fearing that the gearbox is the problem.