I've already posted this in your original thread added here in case you missed it
don't know if you're sorted but i had very similar fault with my '93 yzf750 tried all the things mentioned in this post & more. I ended up taking mine to the Dyno Centre in Northallerton. Stuart the guy who runs it used to race yzf750's in BSB is very helpful & pretty much knows everything there is to know. I'm sure if you give him a ring he'll be able to help. if it helps when speaking to him my bike was the YZF750 with vance & hines paint job i'm sure he'll remember it....
www.dyno-centre.co.uk
Workshop: 01609 760466
Mobile: 07932 493766