96 175 HP problems

I currently own a 95 175ZX Skeeter with a 175 Johnson FastStrike. Ive had a loss of aprox. 5 mph top end a some hole shot. Prop has some minor ticks ; getting it fixed while we speak. however Ive noticed a drop in rpm's at top end from 5800 to 5400. ASny suggestions what could be causing this and what steps should I take. Alsop my alarm came on twice the other day. I shut her down and restarted. She ran fine for awhile; then did it one more time; and ran fine after that. Figured it was a air lock from trying to get on plane. Any suggestions appreciated. Carl

OK not to be "rude" pardon the pun, please read rule 1 at the top of he page. http://xs-s.com/zf/images/smile/emthup.gif Heat and humidity will cause a drop in RPM in a carbed motor. Your motor should also have a system check gauge system depending on YOUR MODEL Number!! Re: Rule 1.

Model# J175GLEDB; Serial # G04061097. It was a cool day in this part of the Ontario about 20 C. Ill keep a eye on the rpm's. When I brought my prop in the guy at the shop said my hub could be slipping. How can I tell if this is happening.