I work for Honda House in Richmond, VA a Honda/Yamaha/Can-Am dealership. During my years in parts (I'm now the company bookkeeper) we did a lot of Honda keys by this method: We've got what can best be described as a set of clipping pliers with lever set cam attachments. Based on the number imprinted on the ignition lock body, we can do replacement keys using a somewhat soft metal Wurth key blank. The downside is that the pliers aren't strong enough to clip the factory (harder steel) blanks. Just checked with my old parts manager, and at our shop we're not set up to do Yamaha (we just took the line on about 18 months ago), but I don't doubt there's a Yamaha dealer who could handle it for you.