Water Skiing and Small RIBs
- Thread starter EME
- Start date
EME
Well-Known Member
Wakeup
Touchee .. I thought you were offering to chauffeur, so that I can laze around in the manner to which I am accustomed - not me skiing!
Touchee .. I thought you were offering to chauffeur, so that I can laze around in the manner to which I am accustomed - not me skiing!
wakeup
Well-Known Member
Wakeup
Touchee .. I thought you were offering to chauffeur, so that I can laze around in the manner to which I am accustomed - not me skiing!
I see, you're offering to take me shark fishing with me on the end of the line
admillington
Well-Known Member
I have been out looking for the same thing today. So the choice seems to be between the Walker Bay as JFM mentioned and the Zodiac Yachtline 340 DL - any advice would be welcomed. Thanks in advance Andrew
jfm
Well-Known Member
The yachtline is very heavy andrew. For the bareboat it's something like 120kg vs 220kg, or something in that range
EME
Well-Known Member
Sorry but a further twist to the saga.
The 'need' also includes monoskiing. Do I take it from earlier answers that this is a 'No' on my theoretical 3.4m 30hp rib? Thanks
The 'need' also includes monoskiing. Do I take it from earlier answers that this is a 'No' on my theoretical 3.4m 30hp rib? Thanks
jfm
Well-Known Member
The issue isn't monoskiing. It's whether you want to deep water start, vs start on 2 skis then drop one. The former needs 100hp+ and the latter needs 25hp, assuming competent skier and say 65kg-80kg body weight (a small child needs less hp of course). Hence, nothing in the 3-3.5m category will be good for deep water start anyway, including the Williams 325 which (nominally) has the highest hp at 104hp. So all the above answers still apply rven if you want to do monoskiing
Anyway, monoskiing EME? Didn't realise you were such a playboy? All becuase the lady loves Milk Tray?
EME
Well-Known Member
Thank for the help! Not so much Playboy Club more Saga Club.
And yes, the Good Lady loves Milk Tray and just about every other brand of chocolate as well. However, if you are suggesting that the consequences of that addiction are in any way connected to the need for considerably more hp to move a rib around, perhaps you might like to tell her that yourself !!
(should be 'winks' of course .. 
: 
Nick_H
Well-Known Member
You could just about start on a single ski behind my 2 stroke jet rib. It took a while and lots of zig zagging about half submerged, so far from perfect, but it was possible! That was using the single ski from a combination pair, and a pro type mono ski has a thinner tail and less lift, so even less perfect. My gut feel is that it may just be possible with a 30 hp 2 stroke outboard, perfectly propped, on a lightweight flat bottomed RIB with a single person on board leaning over the front, although i've never tried it, and I could well be wrong.
As Mapis said, you can't properly ski behind such a small RIB anyway, as you pull the boat all over the place, so its best just to consider it a bit of fun.
As Mapis said, you can't properly ski behind such a small RIB anyway, as you pull the boat all over the place, so its best just to consider it a bit of fun.
wakeup
Well-Known Member
There is a technique for lower powered boats where you circle the skier to get up speed and then pull out and away on the perpendicular to pull the skier out. Not tried it myself and I imagine you need a really experienced skier and driver to make it work safely.
Nick_H
Well-Known Member
Yes, i've heard of that, but also never tried it. I guess it also helps to trail the spare leg, as I did behind the jet rib, but of course you can't do that with both feet in boots.
MapisM
Well-Known Member
Not sure about what that means exactly, but imho by the time you'll be keen on running a slalom course (which is what monoski is all about), you won't be so interested in doing that behind a rib anyway.
Let me explain that a bit better.
Slalom monoski don't necessarily come with the double binding. Also tournament monoski are available with the rear toe strap, and you can use one of them together with another junk ski, just to jump out of the water.
The double binding does allow a bit better control, but I've seen folks closing a slalom course at 38' off with a toe strap ski. Just in case you're not (yet) familar with slalom waterski, that means going round 6 buoys placed at 11.5 metres from the boat, attached to a rope a bit SHORTER than that, and with the boat pulling 36mph - go figure.
So, to do that you actually don't need a double binding ski. But you definitely need a boat which can a) keep a constant speed through the slalom course, in spite of the huge resistance made by the skier after each turn - which is way more than in a deep water start btw, and b) keep a straight course, because such resistance pulls the boat also sideways.
That's the reason why tournament skiboats have 350hp or more, inboard engines, a rope pylon in front of the engine, fixed fins below the keel, etc. And even with that sort of power, they still need sophisticated speed control systems, which automatically adjust the throttle to compensate the ups and downs of the skier pull at each buoy.
Now, just imagine what happens when you're pulling a good slalom skier behind a small RIB. You don't stand a chance to keep a constant speed, let alone a straight track. And the poor chap behind you surely can't make any sort of slalom course, even with a longish rope.
All that said, if as I suppose you just wish to make some relaxed free slalom, in open waters (for a slalom course, a perfectly flat water surface is a must, and no matter how sheltered a bay can be, it'll be hardly flat enough for proper slalom), then the lack of the second binding is the last of your problems, and you can perfectly enjoy monoski starting with a second ski and using the toe strap afterwards.
Besides, if and when you would really fall in love with the double binding, there's one alternative which you might consider: put your bindings on while standing on the swim platform of the main boat, with the rope handle in your hands. The RIB helmsman will then have to start from a side of the boat, going towards the stern and building up some speed. By the time the rope is going to pull you off the swim platform, you'll have to jump in the water, with the ski in front of you, as if you should try to stop the RIB.
That's not easy when you have both feet in the bindings, but it can be done with some practice, allowing you to use also a small power RIB.
Ok, make it a lot of practice, actually...
And also a good RIB helmsman, btw.But that's bound to impress anyone onboard for sure!
MapisM
Well-Known Member
I would not recommend that to anyone. I for one would not even think of trying it, and not just now - also 20 years ago!
The key issue when starting with the pulling boat already going at some speed is to avoid as much as possible the initial water resistance.
And with a good synchronization, you can do that by jumping in the water as I previously described, because after jumping you will only "fall" in the water up to your kees or so, before being pulled out by the boat speed.
With deep water start, it's your whole body which has to overcome the water resistance, and by being snap-pulled, your back is at stake.
Even with a proper skiboat, the driver actually must use some care with the throttle, in deep water start.
I used to ski with some friends who had a 380hp skiboat, and with 3 of us aboard (when returning ashore, without anyone on the rope), the owner once gave full throttle upon start. I was sit astern, and the third guy was in the port seat of the observer, facing aft. But he wasn't expecting such dragster style start. In a second, he was projected at my feet, and just by sheer luck he didn't hit the rope pylon with his head...
No skier on earth would have been able to jump out of the water with that sort of pull.
wakeup
Well-Known Member
We are talking about a 30hp boat not a 380hp monster. Perhaps just taking a run up with the rope half way out would be enough so the rib can get some momentum to climb halfway onto the plane rather than take up the strain on the tow rope then hitting the throttle therefore having to go over the hump and pul the skier out of the hole.
MapisM
Well-Known Member
I see what you mean, but it's a matter of how the acceleration develops.
Ideally, what you want is a constantly increasing pull, and not starting from zero speed, but rather with the boat running at her minimum RPM with the gear engaged.
That's what put less strain on your arms, legs and - most important - your back.
Any other types of start (jump start, beach start, and also the one you mention) are more critical, because starting from zero speed you get suddenly strapped, and the subsequent acceleration is actually poor, because the strong initial pull is only due to the boat inertia, not to its power.
As I said, jump and beach starts are indeed feasible (been there, done that).
But starting from deep water with the the boat launching with the rope slack... Not for me, thanks.
I would even refuse to pull someone, if asked. Too dangerous.
Ideally, what you want is a constantly increasing pull, and not starting from zero speed, but rather with the boat running at her minimum RPM with the gear engaged.
That's what put less strain on your arms, legs and - most important - your back.
Any other types of start (jump start, beach start, and also the one you mention) are more critical, because starting from zero speed you get suddenly strapped, and the subsequent acceleration is actually poor, because the strong initial pull is only due to the boat inertia, not to its power.
As I said, jump and beach starts are indeed feasible (been there, done that).
But starting from deep water with the the boat launching with the rope slack... Not for me, thanks.
I would even refuse to pull someone, if asked. Too dangerous.
wakeup
Well-Known Member
Well I wouldn't be advocating beach starts off the back of the swim platform either, too much to go wrong and I don't think the skier in question is anything other than a leisure skier.
MapisM
Well-Known Member
Can't argue with that.
Actually, I did say "if and when you would really fall in love with the double binding". By which time, he must have built up quite some experience...
Actually, I did say "if and when you would really fall in love with the double binding". By which time, he must have built up quite some experience...
wakeup
Well-Known Member
Can't argue with that.
Actually, I did say "if and when you would really fall in love with the double binding". By which time, he must have built up quite some experience...
How about, you sit the skier with two skis or one on in a ringo. Ringo not attached to the tow line, just the skier holding the two rope.
Build up speed gently being pulled along with bum in ringo until such point the skier can lift their bum off the ringo to the standing position. This should allow the rib to get up to speed, no big jerks or stresses. Obviously would need to go back for the ringo later, but easier to spot than a kick off ski.
mad_boater
Well-Known Member
When I was younger I had a 3.1 Avon with a 15 which pulled me out easily. I later upgraded to a Zodiac 340 with a 30 and that was plenty of power. I wakeboarded - so not much wake to jump with, but great for a youngster to learn.
we had a avon 2.8 rib with a 15hp mercury 2 stroke and a jocky console i could never get my son to waterski behind it he was an adult 12 stone that could waterski!! you could pos pull a child but we never tried it , we could only just pull a ring with an adult , i think you would need minimum 20hp