I would also like to hear some responses. I have a 192 tournament with a 200 hp evinrude 2 stroke. I am getting 5000 rpm at WOT, with the motor trimmed up. The boat is new to me - 1 season. I have the evinrude shop manual, so I know RPM should be 5100 to 5500. I suspect I need to adjust the pitch of the prop and go with something slightly different. Also, the aluminum prop i have that came with the boat is beat to hell. I will take a look at the prop to see if I can determine size and pitch. Good luck with your 192!
For the most real life data available, call Ken at the Prop Gods (http://www.propgods.com). Tell him what boat you have and how you use it and he'll recommend several good options. He will even let you exchange props if you're not happy with the first couple of choices.
I have no connection to Ken other than being a very satisfied customer.
First thing you'll want to do is run your boat under normal load at wot and see where your rpms top out, then check that number with Yamahas recommended top operating rpm. Once you have this info and the measurements ( pitch & diameter) of existing prop, then you'll know how to proceed. You can also do a "google search" for prop selector and find programs that you place your numbers in and they'll select choices of props for your needs.
What Vero said is dead-on. Every boat is going to be a little different - from variances in manufacturing, number of batteries, personal gear, even amount of water that stays in a boat. Always prop your boat based on your normal load, and toward the upper end of the RPM range. Those times that you are a little heavier or lighter can be dealt with at the time.
The prop I have now is in the proper RPM range. I was just wondering if anyone had good luck (performance) with props other than the Yamaha black one i have now. For the boat with the 200 I would probably try a stainless 19" on it first. Just try and find someone that will exchange the prop with another one if it does not work well. http://www.propmd.com/propeller-exchange-program
