Can my weight affect stability?

-- Last Updated: Aug-11-14 12:21 PM EST --

My wife and I had paddled a few times on rented SOT Kayak, even did a nice tour in Cedar Key FL.

After some research we bought a pair of Wilderness Systems Tarpon 100s.we love the features. They seem like good boats.
We have had them out 3 times

She is very stable on the boat. I am not.
I weigh 275lbs could my weight be a factor?

1. would the 12 foot Tarpon with its higher weight rating be more stable
2. if I just keep paddling the 100 will I evenly get better and feel more comfortable.
3. Should I buy something completely different.

Thanks for any advice,
Mike

Yup
The higher you carry the weight, the more “Wobbly” you will feel above waterline. I’m over 6’ but have a short inseam so it’s always been an issue for me. More water time, “Loose” hips, learning to brace, and keeping your head within the confines of the boat all make a difference. Good luck!

Yup
For any conventional kayak or canoe, your center of mass is above the center of buoyancy. A larger mass or a higher center means less stability.



Having a boat that fits your size & weight makes paddling much easier. I see a lot of couples in matching boats who’d be much better off with different sizes. With matching kayaks the smaller partner usually ends up in a boat that’s too big for them, but occasionally it goes the other way.



Width, depth, and volume are often more important than length for a good fit.

That’s a lot of weight for a 10’ boat

– Last Updated: Aug-11-14 1:05 PM EST –

The higher center-of-gravity factor is important, but so is the amount of weight (which Angstrom mentioned already). Think about it this way. The more weight you add to a boat, the more hull volume is submerged, and the more hull volume that's submerged the less the displacement profile changes when the hull is leaned. An extreme example is a boat that's swamped. A swamped boat has virtually no resistance to tipping, because with most of the hull already underwater, almost nothing about the displacement profile changes when it's tipped.

I don't know much about the Tarpon, but I wouldn't be surprised if the 12-footer is pushed beyond its ideal load range too. In any case, you need a bigger boat.

Well…
It has a capacity of 325. You’re nearing that number but not exceeding it, so I’d say its about 50/50 - You’re too heavy and you will get used to it.

You will
probably get used to it.



The first few times I was in mine I was about freaked out with what I percieved as the lack of stability. Yesterday I was putting it up on its side trying to figure out edge turns. I got hung up on a rock in the middle of a riffle, and just pulled the rudder up and humped off. In my defense, there was a power boat with no concept of “no wake” hauling upriver and I didnt focus on where I was going as much as I should have.



At 6’ 255lb I can tell you weight makes a differance, but so does time.

How’s your balance?
I agree with the others that say you’ll get used to it (or more correctly, you’ll learn how to move with it) and that longer may be better for you.



But how’s your balance? Are you sure it’s the boat that’s tippy, or are you wobbly? One exaggerates the other! Focus on doing some balance exercises out of the water and you’ll see a significant difference. I enjoy playing the balance games on the Wii Fit to help, but any balance exercises are worthwhile.

It grows on you
I’m a big guy, too. My balance is not up there with a skateboarder, I’m also not getting any younger. All that said, I started paddling a few years ago. When I first bought a Sit-in boat (WS Pungo 140), I thought I was going to fall in as soon as I left shore. Now, I was surprised to find myself edging up to the gunnels yesterday to make the twisty turns through the meanders of the Ipswich River yesterday.



Loose hip save ships :slight_smile:

Two factors
1) Your mass above the boat - she is probably shorter hence less of her is above the boat.

2) How much the boat sits below its best waterline. All boats, even the most basic rec boats, have point on the hull where things are optimal - the boat’s performance and the stability. Above or below that waterline things start to shift. If you are siting well below the waterline, they don’t shift in your favor in terms of stability.

a load of 325 is not like a body
of 325… A load submerges the hull but the center of gravity is down low too.



Body has a much higher center of gravity… The boat will probably always be squirrely for you. This may impede your skill improvement actually.

Not disputing or side-stepping that fact
There’s no need to point out to me that a high, moving load is worse than a low one. I really thought that part should have been clear enough, and I was only commenting about a less-often-mentioned aspect of the problem.



However, to further illustrate the situation, one of the problems with Old Town’s famously over-stated load ratings for their canoes is that when loaded as deeply in the water as they are when loaded to “capacity”, stability is much worse than when carrying a reasonable load because there’s much less change in the cross-sectional shape of the displaced area when the boat is leaned (so it’s not ONLY a problem with waves over-topping the rails). People talk about primary and secondary stability here all the time, but the whole cause for any resistance to tilting of the boat is the way the cross-sectional shape of displaced area changes with tilt. When such a change becomes minimal, so does stability. Of course, that brings up the topic of small, low-volume sea kayaks, but the users of those boats actually enjoy the lack of stability, as it has some real advantages for them (these boats have very low windage, no real tendency to tilt to match steep waves, and are very easy to roll), but rec-boat users aren’t apt to feel the same about such things.



I can’t say how big an issue this is for this guy with a 10-foot Tarpon, but I think it’s likely a portion of the problem. In any case, personally, I think every short rec kayak looks overloaded when the paddler is near the stated weight capacity and the boat plows along with 7 or 8 inches of draft. Who’s to say that ALL kayak makers assign weight ratings that are any more reasonable than the ratings Old Town applies to their canoes? Who’s actually quantified and tried to make standardized comparisons regarding this stuff? Probably no one.

The 12 ft Tarpon

– Last Updated: Aug-11-14 4:37 PM EST –

Still only has a capacity of 350lb. Add some gear and food, water or other hydration etc, then figure what is optimum vs maximum weight for the boat and even in that boat it may not be ideal, not at 12 ft anyway. A boats maximum load capacity on the tag doesn't mean it's still ideal to paddle that way. Usually not actually. A boat with 375-400lb limit ranges might be better or 350 and longer might be better. Much depends on the boats actual design, where your center of gravity is and so on. But I really think you need a bigger boat anyway.

I'm 6'2" and 220 lb, good sized guy. I have come to realize I need what fits me not what fits on a boat rack or elsewhere on land. I need what will work for me. So far that is the Pungo 140 (which has also a 350 lb limit)kayak and Old Town Camper Canoe ( we paddle tandem mostly but the capacity is over 600lb). But also, I have 0 interest in sit on top boats. With those boats I have room for gear and also capacity to load it. My wife who is smaller and lighter has the Pungo 120 and absolutely loves it. I'm not suggesting that boat, just sayin !

What would be good for you would be if you were able to rent before you buy. Or an outfitter who lets you try out your possible purchase.

max weight
I remember years ago some canoes would have 2 load capacities. It would state how many people can sit in the canoe along with people weight capacity. It would also state total load capacity (people & gear).


Let me ask
What boats were they that you rented and seemed to like ?

Kayaks we rented
Thanks for all the help. I Love this site.



The Kayaks we rented last time at Morro Bay Ca. Were Native Redfish. I looked back on our pics and I see they put my wife on a 10 foot and me on a 12 foot.

The max weight for the Native Redfish models are about the same as the Wilderness Systems boats we have.



I’m thinking the 12foot Wilderness Systems Tarpon maybe a better choice. Maybe the extra 25lbs of load will make just enough of a difference.

And if I keep Kayaking every week maybe I will loose some weight.



Just so everyone knows. We bought these from REI and we are members so we can return mine and trade up to the Tarpon 120 without penalty.



I still really like the features (especially the seat) of the Wilderness System SOT.



Thank again everyone for your feedback.



Mike