Raise the tank. On the right-side you will see your throttle cables and the adjusting screws. The idle screw is the larger screw facing the rear of the bike. The fast idle screw faces the front...it's smaller, than the idle screw.
You may be able to 'back out' the fast idle screw to see if that will help. In my case, I ended up 'bending the tab' on the idle arm so it contacts the fast idle arm sooner. When my fast idle is fully engaged, it's around 6,000 RPM.
I'll see if I have a pic anywhere...
PS - I think stock Fast Idle is around 2500.