They're right. Synthetic is far superior at reducing friction. At around 3000km, I will definitely switch to synthetic. But with a new motor, u want friction so that the piston rings will seal properly with the cylinder walls. U end up with more power, less exhaust gases getting past the rings and into the crankcase, and thus, a longer lasting, trouble free engine. Synthetic oil coats the cylinder walls so well that the piston rings never bed in properly 這是對方說的