the manual says 20,000 km. change the belt ,. I changed my belt at 22,000 km. and then played with the Wt. of the sliders and shaved the variators 1mm. on each side. the belt looked like new , so I put the old belt back on ,I have another 10,000 km. on the old belt , but I watch the condition of the belt, carry tools and spare belt I will see how far I can go with the same belt,