losing rpms's?!?!

[jetfest]

So last season i was pulling 7100 to 7200 rpm now this year i did change my impellar to a solas dynafly but even at the start of this year i was pulling 6900 rpm then i lost some more rpm somehow and was pulling 6700-6600 and now im down to 6200-6400 rpm what could be causing this ive played with my high speed screws to no avail im wondering is this a sign on my reed pedals starting to go? Any ideas?

 

[Scorn800]

I tested a dynafly that pulled my limited down 400rpms.
Has the boat been running crappy? or loss of compression?

 

[jetfest]

it feels pretty good i never tested compression before but i just checked it and its 150 in front and 160 in the rear i do have a jsu head with 29cc domes but im ordering a set of 26cc domes hopfully that will bring compression up but the boat feels pretty good other than the loss of rpm