Belt Drive for Tiger?

Isn't the 800 BMW belt drive too? If they can make it work on a vibey parallel twin and HD's V twin then why not with a smooth triple? Always seemed odd to me that more manufacturers don't go for the belt drive as it offers the advantages of a chain without the lubeing and adjustment, and the maintenance freeness of shaft without the weight and torque reaction. Must be some reason that a simpleton like me doesn't understand.. :-D