I changed my Like 150i belt at 8200 miles. It looked as though it could have easily lasted another 2000 miles, but I changed it anyway. Kymco belt Mitsuboshi 23100-LFB6-900. Two of the rollers were showing obvious flat spots, so I installed a new set. Roller set 22121-GFY6-325. The variator boss was sticky with grease, and the roller cages were dirty but not sticky. Variator plate was not worn, but I did scrub the belt residue from the place where it reached its upper limit of travel. I cleaned everything with spray brake cleaner and installed with no lubricant at all on the boss, shaft, or rollers. Now the scooter is much smoother and quicker at take-off. Top speed increased slightly, too. Noticeable difference in overall performance! Earlier, at 7500 miles, I checked and adjusted the valves. Intake valves were in spec, exhaust vales needed slight adjustment. This made no noticeable difference in engine performance--but I felt better about it!