Hey guys does anybody know the gear ratio of the 6.5hp copperhead and prop size, I am building my own short tail and was trying to get in the ballpark. My plan is to be about 1:63:1 gearing and a 9x6 prop using Martin timing pulleys. thanks

That's close. I seem to recall hearing 1-1.5.

1.5:1 Keep in mind, that 9X6 prop is probably a sub-surface prop. From what I have been told, Copperhead is running a surface piercing prop, even on their 6.5 hp. A few years back, I built 13 hp belt driven motor with a 9X6 prop and a 1.5:1 reduction. On a 1436 with a light load is would run about 15-16 mph at 3800 rpms. It may be too much prop for your 6.5 hp.

Mag10