Low RPMs

I hate to say it but my 200 Yamaha is only turning 4300 rpms. Thought I would go for a quick blast this mornin befroe work, she got right up to 5400 rpms. Turned the boat around to head back in and wouldn't go over 4300.

I did not have a time to tinker with it, but I am going to check fuel first. Seperator and filter under engine cover. Hope that's it.