Here are a few things to consider, coming from a fan of belt drives:
1. Less mess - that's a given
2. Lower maintenance - It's been my experience that the belt stretches a little when brand new but after one adjustment, you don't have to do it again.
3. Durabilty - no links, no kinks and it's durable...my turbo V-rod ran over 200 pases at the drag strip, 625 lb bike and 168 rwhp with no belt problems.
Good idea to check for conversion kits before you decide to fabricate. Also, weren't there several japanese sport bikes that used belts? Kawasaki?
Scott