Rib lose control at 30knots - Page 2

uncle al · 11 October 2011, 20:28

put a heavy weight in the bow but make sure it is secured !!

gazb · 11 October 2011, 21:43

Put some holes in the bottom and make sure you insured it??? Al really .....

Sent from my iPhone using Rib.net

zip · 11 October 2011, 22:21

slow down

wavelength · 12 October 2011, 09:05

ok we seem to have proved that the trim needed using! Perhaps now just try trimming back down a bit til the chine walking goes away. If that doesn't give the desired result then put the bag of sand up front in the bow and play with the trim again. When the trim is right you can feel it is. Trim guages etc are all well and good but the feel of the boat will tell you when its right.

SPR · 12 October 2011, 10:29

Quote:

Originally Posted by wavelength

ok we seem to have proved that the trim needed using!

or RYA powerboat level 2 needed!

S.

9D280 · 12 October 2011, 12:09

Other option of course is to move the fuel tank forward. In a boat of this size, 30L of petrol is a significant concentrated mass. I have 3 tanks - one at the bow, the other two at the stern. I use the bow tank last if I've drunk that much fuel.

Other thought ambling round my mind here - you got a tacho? Your basic setup is not to dissimilar to mine. When I first got the boat it had a way to small pitch prop, and would hit 30 knots ridiculously easily, with me trying to stop the engine going >6500rpm! Changed to an appropriate pitch and it still did 30 odd knots, but it revved at the rated RPM. and didn't try to make 35 knots.....

If you have a tacho, what's it showing at WOT? If not, I wonder if you are running too low a pitch and the engine is screaming it's bits off are you actually taking the boat beyond it's design speed? (is that speed mentioned on the paperwork?)

Jason calleja · 12 October 2011, 15:47

Yes i have 2 tachometer 1 analogue and 1 smart craft and i had only 1 chance to see if the propeller have the right pitch and the outboard reached the 6000rpm at 32knots in a few second and it was trimmed down i had no time to trim out as it chin walked violently but i think more or less it is in the right pitch(14) normally i can’t go over 4600rpm at 26knots as it starts preparing to chine walk. Next time i will try the sand bags and if it will be ok than i will try adding bigger fuel thank and a water thank too. Thanks all for your helpful information

9D280 · 12 October 2011, 16:18

yeah, sounds like you're in the right bapllpark.

Let us know what happens.....

Jason calleja · 31 October 2011, 17:53

Hi all just to let you know that i haven’t forgot to update what happens but here we are out of season and i can’t go to try it if it is not a good weather. I will update what had happened when the weather will permit. Thanks all