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Old 12 February 2014, 16:35   #21
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Country: UK - England
Town: kingsbridge
Boat name: felix
Make: cesar
Length: 3m +
Engine: yam 20hp
Join Date: Aug 2010
Posts: 31
Lol definitely need some more pitch this will also help with bow lift

I'd say I was sold on a cleaver as it's running on the surface but I do like getting airbourne on rollers to I don't play in full surf would I be better with a semi then?
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Old 13 February 2014, 13:19   #22
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Country: UK - Scotland
Town: Isle of Lewis
Boat name: Macleod Special
Make: Mako Thundercat
Length: 4m +
Engine: Yamaha 70ces
Join Date: Jul 2010
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Quote:
Originally Posted by supremesoundz View Post
Lol definitely need some more pitch this will also help with bow lift

I'd say I was sold on a cleaver as it's running on the surface but I do like getting airbourne on rollers to I don't play in full surf would I be better with a semi then?
You'll be fine with a cleaver or chopper. I go out in some big waves and they work just fine - at least as well as my SOLAS. Once you're on the plane they behave almost exactly the same, just with a higher top speed. It's just getting on the plane that they're a bit slower. But even then still faster than most boats!
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Old 12 March 2014, 22:23   #23
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Country: UK - England
Town: kingsbridge
Boat name: felix
Make: cesar
Length: 3m +
Engine: yam 20hp
Join Date: Aug 2010
Posts: 31
heres an update been out a couple times testing since the horrible choppy hail experiance

tried the same setup as before level with hijackers still to much bow lift even trimmed right in and revs were bouncing of the limiter (wasnt breaking out like i thought)

tried all trims even right in was to much?

so i lowered the motor 15mm the next hole tried all trims and once again right in was the best to much bowlift on all others

tried another 15mm lower and as again trimmed right in was the best

out of all settings 15mm lower than the hijackers was the best for control was revving out on the limiter at 6700 ish rpm and the top speed was 39mph the gps must have been up the creek previous test

what we thinking?

spoke to a local prop guy who suggested that because my prop has 20 degrees of aft rake that this is generating bow lift, and this is also using the engines hp to lift the bow reducing power for forward thrust, so suggested losing the bow lift.

he also said to gain some pitch to take the revs down to about 6400 max and adding cupping to the rear of the blade for extra grip


heres a video of how its running 15mm lower than the jackers trimmed right in throttle backed off a little so its not hitting the limiter

https://www.facebook.com/photo.php?v...type=2&theater
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Old 03 April 2014, 09:17   #24
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Country: UK - Scotland
Town: Isle of Lewis
Boat name: Macleod Special
Make: Mako Thundercat
Length: 4m +
Engine: Yamaha 70ces
Join Date: Jul 2010
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sorry late reply!

Bunny props don't like being run too high out of the water as they're not surface piercing props.
You definitely want to get your revs down, so a bigger prop. Don't be afraid of going negative trim, with my big props I have to put a wedge at the top of the transom the engine has negative trim when it's in all the way.

Your prop guy sounds like he knows his stuff, but I wouldn't bother modifying your current propeller, it will never perform as well as a proper cleaver or chopper
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