Just had my second Fourtrak for a couple of months (its on a "S" plate) and after getting a service manual on CD its next service includes a triming belt change. Looking at the "book" the majority of the work to change the timing belt is straight forward, but there is a section where the pulleys are removed, as is what appears to be the cam shaft... is this really necessary?? Can the timing belt be changed by simply removing the old one and replacing it with a new one?? Any help on this would be appreciated!