Hub diameter 4 inches at forward end
Pitch at 6 inch diameter = 15.19 inches
Pitch at 10.5 inch diameter = 13.84 inches
Pitch at 12.5 inch diameter = 17.42 inches
The measurements seem to confirm my hunch that one gets a higher average pitch with this series of Yamaha props. This would explain Chris Collins inability to exceed 4800 RPM with the Yamaha 70HP on his 18 foot Standard, and my inability to exceed 4200 RPM with the same 70 HP engine on my Widebody. By measuring other props I'll know for sure whether I'm right or wrong. I'll be measuring my new Quicksilver prop when it arrives in the mail.
Measuring props is quick and easy on the bench, it has been done a particular way since the invention of the propeller. Unfortunately, you won't find the method in Gerr's current propeller book. Fortunately, there are many free descriptions of the method on the internet. Here's a good example: