When does the RAVE valve activate.

[drjack]

Taking our boat out for a leisurely run around the bays, with flat water all day. It's a 951 with complete rebuilt carbs and all tempo lines replaced, non ethanol fuel used.
While running around the 3500 rpm mark, I can detect the occasional lowering of power or slight rpm drop. If I hit the throttle a bit, the engine quickly reacts to a higher rpm and holds. Anything below 3000 rpm, engine is stable also.
Are the RAVE valves activating somewhere in this 3000 to 4000 rpm range, and should I detect a change in engine performance when the valves move?

 

[Sportster-2001-951C-Stock]

I believe my RAVE valves open just over 5,000, actually about 5,200 best I can tell by feel. There seem to be a little kick there.

There's another more appreciable kick when the throttle reaches about 80% throttle where the throttle position switch located on the throttle cable makes, this add ignition timing advance and that kick is more pronounced.

My feeling is, your carbs are lean thus this is a lean hesitation.