Most rolling chassis parts and controls are very interchangeable between trials bikes, things like brakes, wheels and suspension assemblies are largely common between models and even manufacturers. We can almost tell you what all parts are going to regularly wear out and need replacement, wheel bearings linkage bearings, fork seals and slide bushings, brakes, levers, tires and chain. Most buy a spare air filter so you can always have one clean, oiled and ready to use. Tether kill switch is normally an add-on to trials bikes and a component that can often cause problems after some crashes. Being a 2007 model you should be replacing all fluids, brake fluid will be done by now if not already replaced.