Maybe a conversion to EFI. Some years ago when I had a Suzuki SV650 I got thinking about changing the XZ550 to EFI, much the same as the second generation SVs. I found a set of throttle bodies with injectors for pretty cheap, about $50-60. if I recall correctly, so I got them and began scheming. The problem with my scheme is that it got a bit heavy in technical details and the modifications I would have to make on the XZ for cam position sensor, crank sensor, O2 sensor, mass air flow/temp etc. Then there is the higher fuel pressure ( a mimimum of 46psi) and all that entails, plus the different angles of the V motors meant the brackets holding the throttle bodies would have to be significantly modified so the throttle bodies could be positioned correctly. It was easier for my old brain to grasp the concepts related to carburetors rather than all the necessary aspects of an EFI system. I know it isn't rocket science, but it turns out to be a bit more complicated than I was ready to tackle. Maybe it isn't as difficult as I made it out to be, but maybe it is more difficult. So I went the route with FZ/YZF carbs, though I am still a long way from making this project run. Anyway, the point I was going for is that the EFI system does the air/fuel control automatically. Just a thought.