Well had a good day at North Berwick on Sunday . First run in calm waters gps was reading 30 knots with my 50 on the back and rev sitting at 6k could have went more but my sensible head kicked in..............
Thats duff info. with the right balance and prop you should be able to achieve 39
I had a 10.5 x 15 four bladed spitfire prop on mine and 39.4 was its best on slack water. Aj hits 34.5 with his 40 two stroke again with the same design prop!
__________________ Member of S.A.B.S. West Country Division
Since I've had my carbs cleaned out and my Mercury 50 is running well I also get 6k indicated on my rev counter. However given that when the engine is off it indicates ~1k rpm I'm unsure whether the rev counter is reading well. Waiting for some calm water to do some top speed testing. I'll also have a poke about to see what the fitted prop is and how this compares to the spare that came with the boat.
Tim, it is common for tach to show the rpm when the engine was turned off. If you have a key turning to on (but not as far as start) will normally reset it.
Don't prop for top speed, that's hairy chest medallion wearing shit. Any tosser can put the throttle on the end-stop on a flat calm day and take pics of the GPS.
Real men prop for grunt. Our's will do 32knts WOT with a 14 3/8 s/s prop. It leaps onto the plane and is as punchy as ferk in any kind of sea.
Don't prop for top speed, that's hairy chest medallion wearing shit. Any tosser can put the throttle on the end-stop on a flat calm day and take pics of the GPS.
Real men prop for grunt. Our's will do 32knts WOT with a 14 3/8 s/s prop. It leaps onto the plane and is as punchy as ferk in any kind of sea.
Bet thats what the bloke who's tender you nicked called you or perhaps he used stronger words
Quote:
Real men prop for grunt
and if anybody is propping for top speed then don't as mollers will hate it!
__________________ Member of S.A.B.S. West Country Division
I don't have ptt so I can't change my trim on the go but all I meant was if the outboard is revving at 6000 and there was still some throttle left a bigger prop would be the way to go.
I think I have my boat fairly well balanced but not got near 40 knots yet. I only have a standard ali prop though and not enough ribs around these parts to compare it to.
Out of interest where do most others place their weight around the boat? Mine is a bit twitchy at 30 knots plus unless fairly calm.
Mellifera
with the right balance and prop you should be able to achieve 39
