Optimal RPM range for Yamaha 30 HP 2 stroke

[Mallards Only]

I recently purchased a used Yamaha 30 HP and after a number of boat mods and adding a Tiny Tach finally got it on the water to see what kind of RPM's I'm getting. This thing is running around 9000 RPM at WOT. What is the ideal range for this motor? I don't have the manual. Am I under-propped?

[DRAGRACR]

What rpm are you seeing at idle? More than likely your setting is not correct on the tiny tach. I have tried 2 different brands of them, now they are sitting in my tool box. If you have a 2 cylinder you MIGHT get it to work but if you have a 3 cylinder do yourself a favor and buy you a marine tach either analog or digital. I did the same thing and now I own a yamaha digital and saved myself a lot of headache and it works perfect.

[Mallards Only]

Hadn't really considered that it might be the tach. I'll run it on the hose tomorrow and get back to you on the idle RPM's.

[DuckLn]

What yamaha digital?

[DRAGRACR]

The one I bought was Pt # 6Y5-8350T-83-00. There are others that will work but this is the one I have.

[FrenchPhil]

Somethings not right. Most smaller 2 strokes should be around 5500-6000 rpm at WOT .