Have you removed your fuel tank lately? It's a common issue that when you put the tank back on it pinches the braided fuel line. Members report that their bikes would struggle to go above 8500rpm when the fuel line was pinched. You could also make the same mistake I made the other day and that was to not attach the fuel line back onto the tank properly. I noticed the problem when the bike seemed down on power through the mid range and cut out at 12,500rpm.