With a 9.5x10 prop I'm seeing 25mph on a 14' jonboat. Now I'm cheating some with the 15hp carb, but what is the average top speed most 9.9's get with the same setup?
Happy, I'd be ecstatic....like wood.... wow 25 ..on 14' jonboat and 9.9.....is the GPS or fish finder speed.....sounds like its on methamphetamines not gas and oil
DEIFan,<br /><br />Reminds me of this old 125cc two-stroke motorcyle I used to have when I was 16. It wasn't much in the speed department. One day, I decided to try something. I got a can of model airplane fuel and put it in the empty gas tank of the little Harley Davidson Hummer.<br /><br />It fired right up...would only run at full throttle...no idle, so I quickly shut it down. Next time, I push started the old bike, so I'd be in gear when it fired up.<br /><br />Long story short: Apparently the old Harley 2-stroker wasn't designed to turn 10,000 RPM. I did manage to get through all three gears and reach speeds never imagined on that bike. That was its last ride. My dad was not amused. Not at all. I still love the smell of castor oil, though.<br /><br />NOTA BENE: Do not try this fuel mix on your classic Johnnyrude. It is unlikely to produce good results.
Initial results may be good however the longevity is in question... <br /><br />Chris ...was the MPH reading from GPS or Fishfinder ?? ...Sounds like your setup is going to be hard to beat....
Hmm, 25mph with a 10" prop suggests you're winding it out to over 6500RPM (12:29 gear ratio). If those number are accurate then you may well do better with a steeper prop. A tach will tell for sure.
I did take my Garmin Etrex out with me for speed measurements. Yesterday with another guy in the boat and some gear we were seeing 20mph with some slight chop and into the wind. I've checked the GPS against those radar doodads on the side of the road ('Your Speed') and my own truck speedo and it seems to be pretty darn accurate.<br /><br />So 25mph GPS indicated is good, eh? Fantastic. <br /><br />I'll look at getting a tach soon so I don't wind it out too much. Do they even make a 9.5x11 or 12?
<br /><br />Chris ...was the MPH reading from GPS or Fishfinder ?? ...Sounds like your setup is going to be hard to beat....