Where to attach a tube rope...

[sliver]

I'll start by being upfront. I'm not a big fan of tubes. I bought one just before we ordered our 'Bu and have yet to pull it behind it.

With that said, when I have pulled tubes with any ski boat, I have always used the rear tow bar on the stern. I could be wrong but, if I'm not mistaken, that is the main function of this tow location. Plus, it gives you more control over the tube.

[tgaugh]

We are guilty of using the pylon and tower.

[RoverOn]

We are guilty of using the pylon and tower.

My first response is to put it around your neck

But seriously:

Pylon is the strongest....would not do two people off of the rear tow point.

If I am going to really toss around two people...I use the pylon.

1 hardcore or 2 easy riders and I use the tower.

Dave

Edited June 20, 2006 by RoverOn

[auto]

Tie one end of rope to drivers neck, the other end to tubers neck proceed at high speed.

[tgaugh]

Oh, and make sure all 4 bumpers are hanging off the side. Proceed at WOT near all righteous wake-boarding think-they-own-the-lake types.

[auto]

Proceed at WOT near all righteous wake-boarding think-they-own-the-lake types.

Hey i resemble that

[tgaugh]

Don't we all.

[Dan P]

Pylon is the strongest....would not do two people off of the rear tow point.

I don't agree that the pylon is stronger than the bar on the transom. I've always tied inflatables to the transom.

[sliver]

To my knowledge, the transom is the strongest point... but, as I said before, ICBW....

[gooddog]

In light of my friends accident and the kind of stress placed on the boat because the tube went upside down and dug in, and IF I were going to pull one, I would connect it to the transom eye. I wouldnt want to have stress cracks around the rear tow bar. I guess if its just little kids that you aren't trying to kill, the rear tow bar would be fine and provides a better pull for a tube rider. But I would only want to pull someone I wanted to kill. j/k

[NorCaliBu]

I prefer to tie the tube to someone else's boat... ...or better yet, to the dock. Makes a good floating island for the kids to play King-of-the-Tube.

[sliver]

Malibu says 400# off the rear thing, 1000# off the pylon. IIRC, FWIW

That's interesting. I too would think the lifting rings are the strongest points.

[Birm]

Pylon is the strongest....would not do two people off of the rear tow point.

I don't agree that the pylon is stronger than the bar on the transom. I've always tied inflatables to the transom.

To my knowledge, the transom is the strongest point... but, as I said before, ICBW....

The lifting rings must be stronger than the grab-handle tow point--they lift the boat with those things.

Malibu says 400# off the rear thing, 1000# off the pylon. IIRC, FWIW

Pete, Andy or Matt may want to chime in here...On the tour last week Pete specifically asked what was the strongest tow point. I think the answer that we received was the transom tow hooks. We actually looked at how they re-inforce the transom and the rear pylon. Both receive a heck of a lot of extra material for support. More material and fiberglass is placed around the tow hooks and the pylon. Based on seeing this, I would feel comfortable towing a tube with the pylon.

By the way, I think tubes are great. I have seen some incredible smiles on young kids faces who are being towed on a tube with an adult. I think it is a really fun thing to do for those who aren't quite ready for boarding or skiing. Its also fun every now and then for us grown ups.

[RoverOn]

To my knowledge, the transom is the strongest point... but, as I said before, ICBW....

Lifitng rings on transom = STRONG

Grab bar tow point = no tubes

[RTS]

Lifting ring on the transom may be strong enough to lift the boat out of the water, but that's a different story than their ability to withstand forces in the horizontal direction. In the vertical, there's alot of fiberglass to take the weight. Also notice they angle the hooks are mounted at, they are not vertical, which spreads the lifting force over even more fiberglass.

Take a piece of paper and hold it with one finger on one side and one finger on the other side (paper between your finger tips, fingers horizontal, paper vertical) Note how you can hold the paper vertical without it deforming. Now rotate so your fingers are vertical and see how the paper folds over? That's the problem, overstessing the fiberglass, bowing it out, so to speak. The transom is not as strong in that direction as it is in the vertical.

Now, that being said, and Malibu's claim that the grab rail can take 400 lbs, you should be able to tow quite a tubing party from it. The 400lbs is not the weight of the rider, it's the force the rail can take. Load up your favorite tube with a 200 lb man, and you'd have to be subjecting him to 2 g's to have the 400 lbs force at the grab rail. 2 g's is more force than you think.

Plus, the only way to try to generate those forces is to be slinging the tube out to the side, and the transom would get stronger if the forces were applied in that direction (see example above)

So go ahead and tow from your grab rail...as said earlier, it frees up space in the boat, and unless you drive like a maniac, towing a maniac, I don't think you could put 400 lbs of force on the rail if you tried...

EDIT: I just read the above post regarding the tube digging in, and agree that could cause some overstressing on the transom...

Edited June 20, 2006 by rts

[sliver]

The point of this topic was to educate myself and others as to the best/safest way to pull a tube.

You make some great points rts!

[RTS]

The 400lbs is not the weight of the rider, it's the force the rail can take.

I think when someone quoted 400/1000 they meant weight of person(s) being towed. That already already allows for the dynamic forces present when pulling that weight through water. The pylon has been tested beyond 2,200# of pressure.

That being the case, I'd be pretty comfortable pulling tubes from the grab rail, just don't exceed 400 lbs total weight. I regularly pull two tubes at a time from there, but it's young kids that are on them, they don't weigh much, and I am not trying to have a death match out behind the boat. I keep it below 20 MPH or so...

And I agree with the comment above that tubes serve their purpose. It's a good way to have a youngster (or adult who hasn't been on boats) get comfortable with the idea of being alone in the water away from the boat, a "skill" they will need to master before they can get skiing (or wakeboarding, if that's your cup of tea)

[gonorth]

Interesting this comes up now. I have always pulled tubes from the pilon (Response - in the center). But I don't get a lot of whip from that position. This weekend I will be pulling my wifes nepheu and he is a real hot shot when it comes to his claims to be able to stay on a tube. He has never been behind an inboard so I fully intend to have him in the water in about 5 seconds, give or take one. My technique is one I used to use back in high school when we did slolom starts with a 95 hp outboard and used the leverage you get by starting to the side of the boat. I start the tube from the side, using medium throtle accelarate straight for about 2 seconds to churn up a decent wake then turn hard and provide full throtle at the same time whiping the skier over that big wake. It's a 'killer'. But I was seriously thinking a tie from the transom somewhere would provide a lot more whip. Guess I will use the grab handle. Then the rest of the weekend we can leave the tube tied to the dock.

[Chia]

Lifting ring on the transom may be strong enough to lift the boat out of the water, but that's a different story than their ability to withstand forces in the horizontal direction. In the vertical, there's alot of fiberglass to take the weight. Also notice they angle the hooks are mounted at, they are not vertical, which spreads the lifting force over even more fiberglass.

Take a piece of paper and hold it with one finger on one side and one finger on the other side (paper between your finger tips, fingers horizontal, paper vertical) Note how you can hold the paper vertical without it deforming. Now rotate so your fingers are vertical and see how the paper folds over? That's the problem, overstessing the fiberglass, bowing it out, so to speak. The transom is not as strong in that direction as it is in the vertical.

Now, that being said, and Malibu's claim that the grab rail can take 400 lbs, you should be able to tow quite a tubing party from it. The 400lbs is not the weight of the rider, it's the force the rail can take. Load up your favorite tube with a 200 lb man, and you'd have to be subjecting him to 2 g's to have the 400 lbs force at the grab rail. 2 g's is more force than you think.

Plus, the only way to try to generate those forces is to be slinging the tube out to the side, and the transom would get stronger if the forces were applied in that direction (see example above)

Your analogy to holding a piece of paper is interesting, but if you were holding a piece of fibreglass, it would not matter which way it was held.

So go ahead and tow from your grab rail...as said earlier, it frees up space in the boat, and unless you drive like a maniac, towing a maniac, I don't think you could put 400 lbs of force on the rail if you tried...

EDIT: I just read the above post regarding the tube digging in, and agree that could cause some overstressing on the transom...

I think i disagree with the part about the transom hooks not being strong on the horizontal. I take my boat in each year for power polishing and they put it on a rack that holds it by the bow hook and transom hooks. Then they rotate the boat to almost on its side to power polish the bottom. That would be more stress on those hooks than a body on a tube, wouldn't it?

your analogy to holding a piece of paper is interesting, but if you were holding a piece of fibreglass, the orientation would not matter, the fibreglass would retain its shape.

Edited June 21, 2006 by Cervelo

[RTS]

But imagine your horror if you went to check on the polishing job, and the boat was suspended nose down by only the the transom eyes...like a dead great white shark.

When I say its not as strong in the horizontal, I guess I should clarify by saying not as strong in the horizontal, parallel to the keel.

And I'm not saying it's weak in that direction...just not as strong.

And re: the orientation of the fiberglass, try this experiment....

Take a 1' x 1' x 1/2" thick piece of fiberglass. Set it up on two bricks 10" apart vertically, like a window pane, and then try to bust it by stomping down on it from the top.

Then lay it flat on those two bricks and stomp on it in the middle from the top.

I think you'll agree that you have a much better chance of harming the integrity of the glass in the latter case, and that the orientation does matter. When you lift you boat vertically by the eyes and front ring, you are subjecting the transom fiberglass to forces in the direction it is strongest. The opposite is true when towing from the eyes.

Edited June 21, 2006 by rts

[Chia]

But imagine your horror if you went to check on the polishing job, and the boat was suspended nose down by only the the transom eyes...like a dead great white shark.

When I say its not as strong in the horizontal, I guess I should clarify by saying not as strong in the horizontal, parallel to the keel.

And I'm not saying it's weak in that direction...just not as strong.

And re: the orientation of the fiberglass, try this experiment....

Take a 1' x 1' x 1/2" thick piece of fiberglass. Set it up on two bricks 10" apart vertically, like a window pane, and then try to bust it by stomping down on it from the top.

Then lay it flat on those two bricks and stomp on it in the middle from the top.

I think you'll agree that you have a much better chance of harming the integrity of the glass in the latter case, and that the orientation does matter. When you lift you boat vertically by the eyes and front ring, you are subjecting the transom fiberglass to forces in the direction it is strongest. The opposite is true when towing from the eyes.

You are essentially trying to break a 1' thick (albeit only 1/2" wide) piece of fibreglass as opposed to breaking a 1/2" piece of fibreglass, of course it will be harder to break. The thickness of the fibreglass around the the transom hooks is all the same.

[BlastRlxi]

It seems like people are confusing the transom eyes (the rings that hold your boat to the trailer) and the transom ski tow/grab rail located in the center of the transom. The transom eyes are very strong. They are the best spot to tow another boat from and will easily hold the boat suspended in air. However, the transom ski tow/grabrail is nowhere near that strong and is weaker than the pylon but better than a tower for pulling a tube.

[GoldschlagerVT]

But imagine your horror if you went to check on the polishing job, and the boat was suspended nose down by only the the transom eyes...like a dead great white shark.

When I say its not as strong in the horizontal, I guess I should clarify by saying not as strong in the horizontal, parallel to the keel.

And I'm not saying it's weak in that direction...just not as strong.

And re: the orientation of the fiberglass, try this experiment....

Take a 1' x 1' x 1/2" thick piece of fiberglass. Set it up on two bricks 10" apart vertically, like a window pane, and then try to bust it by stomping down on it from the top.

Then lay it flat on those two bricks and stomp on it in the middle from the top.

I think you'll agree that you have a much better chance of harming the integrity of the glass in the latter case, and that the orientation does matter. When you lift you boat vertically by the eyes and front ring, you are subjecting the transom fiberglass to forces in the direction it is strongest. The opposite is true when towing from the eyes.

You are essentially trying to break a 1' thick (albeit only 1/2" wide) piece of fibreglass as opposed to breaking a 1/2" piece of fibreglass, of course it will be harder to break. The thickness of the fibreglass around the the transom hooks is all the same.

I agree with BlastRlxi. The transom hooks (not the grab hook) is where malibu says if you're going to tow another boat, that's where you want to do it from. I'm going to go out on a limb here and say that if you can tow a 3,500lb boat with those hooks, you can tow a tube with 1 or 2 people on it without any problems.

[Birm]

But imagine your horror if you went to check on the polishing job, and the boat was suspended nose down by only the the transom eyes...like a dead great white shark.

When I say its not as strong in the horizontal, I guess I should clarify by saying not as strong in the horizontal, parallel to the keel.

And I'm not saying it's weak in that direction...just not as strong.

And re: the orientation of the fiberglass, try this experiment....

Take a 1' x 1' x 1/2" thick piece of fiberglass. Set it up on two bricks 10" apart vertically, like a window pane, and then try to bust it by stomping down on it from the top.

Then lay it flat on those two bricks and stomp on it in the middle from the top.

I think you'll agree that you have a much better chance of harming the integrity of the glass in the latter case, and that the orientation does matter. When you lift you boat vertically by the eyes and front ring, you are subjecting the transom fiberglass to forces in the direction it is strongest. The opposite is true when towing from the eyes.

You are essentially trying to break a 1' thick (albeit only 1/2" wide) piece of fibreglass as opposed to breaking a 1/2" piece of fibreglass, of course it will be harder to break. The thickness of the fibreglass around the the transom hooks is all the same.

I agree with BlastRlxi. The transom hooks (not the grab hook) is where malibu says if you're going to tow another boat, that's where you want to do it from. I'm going to go out on a limb here and say that if you can tow a 3,500lb boat with those hooks, you can tow a tube with 1 or 2 people on it without any problems.

I dont get it. Why not just use the pylon?

[UWSkier]

We've had 5 tubes on our pylon at once. We've had 6 slalom skiers on our pylon at once. Last year at the Malibu open, I saw a Response with the Hammerhead 383 completely bog down and stop completely at WOT trying to pull a pyramid dock start. They were all being pulled from the pylon.

The pylon is stronger than any motor Malibu puts in their boats... Just tow from there and you'll be fine...