I just changed mine at 82k. It depends on how hard the car was driven, but I don't recomend letting it go past 90k. They use 105k as a reference for light-moderate driving. Changing it is a labor intense job..... the engine mounts have to be removed, front of the engine torn appart. Your Honda dealer will typically charge 500.00 - 700.00 for parts and labor (replace timing belt, counter ballance belt, water pump, both accessory belts, cam adjustment). You can obviously get it cheaper at a garage, but make sure they are familiar with Hondas. I did mine with the help of my uncle who is a certified ASE for all makes and works out of his house, so he had the tools and equipment to do it right. I spent about 300.00.