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"Michael Daly" wrote in message ... On 15-Jun-2005, "rick" wrote: Again, how does a longer kayak "overall" not have a longer waterline for the same type hull The original poster said nothing about "same type hulls." He provided two overall lengths and asked for an assessment of how the speed would compare. I correctly stated that one cannot determine that from the information on overall length. But for a given hull design, it still looks to me that that will be the major factor according to the sites I posted. You're ignoring the data on the graph. The data comes from Sea Kayaker magazine and clearly shows that there is no correlation between overall length and resistance. Why do you keep insisting that there is? ==================== Beause you've failed to make your case against the other sites I have read. See also: http://www.kayakforum.com/cgi-sys/cgiwrap/guille/wiki.pl?The_Myth_Of_Length No, I'm posting web sites that state the opposite of you, not MY opinion. Which of course you have snipped. Try reading a book on the hydrodynamics of hulls. C.A. Marchaj's "Sailing Theory and Practice" is a good one. You can also stop assuming that overall length and waterline length are interchangable. I was seriously asking for data. I gave you some. It shows that there is no correlation between resistance and length for 24 common sea kayaks that have been reviewed in Sea Kayaker magazine. ======================== No, you did not answer the question I asked. You snipped it out, and ignored it. Why is that? Mike |
"rick" wrote in
ink.net: "Michael Daly" wrote in message ... On 15-Jun-2005, "rick" wrote: Again, how does a longer kayak "overall" not have a longer waterline for the same type hull The original poster said nothing about "same type hulls." He provided two overall lengths and asked for an assessment of how the speed would compare. I correctly stated that one cannot determine that from the information on overall length. But for a given hull design, it still looks to me that that will be the major factor according to the sites I posted. You're ignoring the data on the graph. The data comes from Sea Kayaker magazine and clearly shows that there is no correlation between overall length and resistance. Why do you keep insisting that there is? ==================== Beause you've failed to make your case against the other sites I have read. Actually a very good case was made by posting information from a credible source on sea kayak length. Of the three sites you posted one was about Canoes from someone named Cliff Jacobson. What are his credentials? The other two site specifically talk about water line lenght, not overall length, a point that Mike has stressed throughout this thread. The original poster asked for a speed comparison of two kayaks of similar overall length, and Mike correctly pointed out that a speed comparison can not be made based on overall length. In response you post three sites, one about canoes and the other two which support Michaels contentention that waterline length (not overall length) is an influencing factor. See also: http://www.kayakforum.com/cgi-sys/cg...?The_Myth_Of_L ength No, I'm posting web sites that state the opposite of you, not MY opinion. Which of course you have snipped. No, you posted two web sites which agreed with him. Try reading a book on the hydrodynamics of hulls. C.A. Marchaj's "Sailing Theory and Practice" is a good one. You can also stop assuming that overall length and waterline length are interchangable. I was seriously asking for data. I gave you some. It shows that there is no correlation between resistance and length for 24 common sea kayaks that have been reviewed in Sea Kayaker magazine. ======================== No, you did not answer the question I asked. You snipped it out, and ignored it. Why is that? I read back through the thread and the only question you asked was related to canoes, not sea kayaks, which is what the original poster was aksing about. While Michael didn't answer the question directly (or maybe just hasn't given the answer you want to hear) he did answer it by posting the comparison of overall length vs water line length for 24 sea kayaks. I don't think anyone is going to deny that a kayak with a 18' overall length is going to have a longer waterline than a kayak with a 14' overal length but the original poster was asking about two boats with that much of a difference in overall length. The differences in overall length in the boats that the OP was asking about was only about a foot and a half and it is entirely possible that the boat with the longer overall length would have a shorter waterline length, or at least be close enough that the water line length would have a negligable impact in kayak speed. That's the point that Michael has been making all along but you seem more interested in just arguing by tossing out red herrings that are irrelevant to was the OP was asking. |
"John Fereira" wrote in message .. . "rick" wrote in ink.net: "Michael Daly" wrote in message ... On 15-Jun-2005, "rick" wrote: Again, how does a longer kayak "overall" not have a longer waterline for the same type hull The original poster said nothing about "same type hulls." He provided two overall lengths and asked for an assessment of how the speed would compare. I correctly stated that one cannot determine that from the information on overall length. But for a given hull design, it still looks to me that that will be the major factor according to the sites I posted. You're ignoring the data on the graph. The data comes from Sea Kayaker magazine and clearly shows that there is no correlation between overall length and resistance. Why do you keep insisting that there is? ==================== Beause you've failed to make your case against the other sites I have read. Actually a very good case was made by posting information from a credible source on sea kayak length. Of the three sites you posted one was about Canoes from someone named Cliff Jacobson. What are his credentials? The other two site specifically talk about water line lenght, not overall length, a point that Mike has stressed throughout this thread. The original poster asked for a speed comparison of two kayaks of similar overall length, and Mike correctly pointed out that a speed comparison can not be made based on overall length. In response you post three sites, one about canoes and the other two which support Michaels contentention that waterline length (not overall length) is an influencing factor. ======================= I never claimed otherwise. He keeps asserting that overall length is no indicator at all of waterline length. Most people will recognise that typically the longer the boat, the longer the waterline. In the discussion I was commenting on, he declared length meant NOTHING to speed. He claimed 'many factors' contribute to speed, but has yet to state what those are, even after being asked. Again, I've never denied 'waterline' lenngth, but going on about symantics doesn't prove anything. See also: http://www.kayakforum.com/cgi-sys/cg...?The_Myth_Of_L ength No, I'm posting web sites that state the opposite of you, not MY opinion. Which of course you have snipped. No, you posted two web sites which agreed with him. ================= No, I don't think so. He claimed "many factors" affect speed, but length wasn't one of them. Try reading a book on the hydrodynamics of hulls. C.A. Marchaj's "Sailing Theory and Practice" is a good one. You can also stop assuming that overall length and waterline length are interchangable. I was seriously asking for data. I gave you some. It shows that there is no correlation between resistance and length for 24 common sea kayaks that have been reviewed in Sea Kayaker magazine. ======================== No, you did not answer the question I asked. You snipped it out, and ignored it. Why is that? I read back through the thread and the only question you asked was related to canoes, not sea kayaks, which is what the original poster was aksing about. ========================== Boats are boats. Being covered on top has no relation. While Michael didn't answer the question directly (or maybe just hasn't given the answer you want to hear) he did answer it by posting the comparison of overall length vs water line length for 24 sea kayaks. ===================== No, he ignored, and snipped out the direct question I asked, and repeating assertion about length does not answer the question I asked, which was what are the 'many factors', since length plays no part, in the speed of a boat. I don't think anyone is going to deny that a kayak with a 18' overall length is going to have a longer waterline than a kayak with a 14' overal length but the original poster was asking about two boats with that much of a difference in overall length. ======================= Looks like Mike did. He claimed that overall length did not correlate to waterline lenght. The differences in overall length in the boats that the OP was asking about was only about a foot and a half and it is entirely possible that the boat with the longer overall length would have a shorter waterline length, or at least be close enough that the water line length would have a negligable impact in kayak speed. That's the point that Michael has been making all along but you seem more interested in just arguing by tossing out red herrings that are irrelevant to was the OP was asking. ========================== No, you seem to be selectivly reading what you want. I have asked him what other factors are involved, he has refused to answer, and continues his symantics about 'length'. |
OK, I'll toss another question...
How much faster would be the Manitou (12'10" by 25") than the Drifter (12'7" by 32.5")? Tell me in percentage... |
On 16-Jun-2005, "rick" wrote: Beause you've failed to make your case against the other sites I have read. How about - the sites you identified are irrelevant to the discussion. Just because they talk about waterline length means nothing in the context of comparing waterline length and overall length. No, you did not answer the question I asked. You snipped it out, and ignored it. Why is that? Probably because your line of questions is not contributing to the discussion. You just want to nit-pik on trivia. The _fact_ is that overall length is not a reasonable indicator of kayak performance. Waterline length may be, other factors being equal. If you can't deal with that, there's nothing I can do about it. Mike |
On 16-Jun-2005, Peter wrote: No, it clearly was never true. Even taking the subset of kayaks you chose, you calculated a correlation coefficient of 0.79 indicating a very high level of correlation. Not high enough and nowhere near the level you claimed without any proof. The _fact_ is that at that level, the differences in overall length between two kayaks are comparable to the differences in overall length and waterline length in one kayak. Clearly a much higher level of correlation is required than 0.79. In this case, the mathematic definition of correlation has to take a back seat to the more pragmatic need to produce information that is of some value. If all kayak types were included the correlation would be even higher. Your claim - how about something resembling proof? Your last guess of 0.95 was based on nothing. In the particular case of the two kayaks considered by the OP, their lengths only differed by about 2' but the hull shapes appear to be quite similar with no obvious difference in overhang. Therefore it's highly likely that the Biscyne which is longer overall will also have a longer waterline length. Even if it does have a longer waterline length, that still does not guarantee that the speed is higher. Hydrodynamics trumps simple geometric parameters. How about offering something of value instead of simply trying to not-pick? Like offering some data that actually backs up you ludicrous claim that what I am saying is false. Mike |
On 16-Jun-2005, "rick" wrote: He claimed "many factors" affect speed, but length wasn't one of them. Where exactly have I ever said that waterline length doesn't affect speed? I said that overall length is not a usable indicator because of the great variation between overall length and waterline length. I demonstrated that with a scatter graph of the two parameters for _real_ sea kayaks. Mike |
Michael Daly wrote:
Like offering some data that actually backs up you ludicrous claim that what I am saying is false. You already provided it yourself. After first making the claim that there was "no correlation" between LOA and LWL, you later provided data indicating that the correlation was 0.79 which clearly showed your initial statement to be false. QED. |
On 16-Jun-2005, "rick" wrote: I don't think anyone is going to deny that a kayak with a 18' overall length is going to have a longer waterline than a kayak with a 14' overal length ======================= Looks like Mike did. He claimed that overall length did not correlate to waterline lenght. Lookee, Lookee what I found on the web site that someone posted with Sea Kayaker magazine data: Prijon*Calabria Current Design Andromeda LOA 4.42m (14.5ft) 5.26m (17.25ft) LWL 3.96m (13 ft) 4.19m (13.75ft) Drag 16.7 lb 18.0 lb So here we have two _real_ sea kayaks, one that is more than 17 foot long and another that is over 14 feet long (one 19% longer) yet their waterline lengths are 13 and 13.75 feet respectively (one only 6% longer). Note in particular that the _shorter_ kayak has less resistance at 4.5 knots. Is this what you call a high correlation between LOA and LWL? Does this prove that long kayaks are faster? Mike |
"Michael Daly" wrote in message ... On 16-Jun-2005, "rick" wrote: He claimed "many factors" affect speed, but length wasn't one of them. Where exactly have I ever said that waterline length doesn't affect speed? I said that overall length is not a usable indicator because of the great variation between overall length and waterline length. I demonstrated that with a scatter graph of the two parameters for _real_ sea kayaks. Mike ====================== OK Not getting anywhere I see. You still won't/can't answer the question I asked. Thanks anyway. I'll just wait or somebody else, someday... |
"Michael Daly" wrote in message ... On 16-Jun-2005, "rick" wrote: Beause you've failed to make your case against the other sites I have read. How about - the sites you identified are irrelevant to the discussion. Just because they talk about waterline length means nothing in the context of comparing waterline length and overall length. No, you did not answer the question I asked. You snipped it out, and ignored it. Why is that? Probably because your line of questions is not contributing to the discussion. You just want to nit-pik on trivia. ==================== No I did not. I asked you to explain YOUR statement about the "many factors" that affect speed other than length. You are the one nit-picking on definitions. The _fact_ is that overall length is not a reasonable indicator of kayak performance. Waterline length may be, other factors being equal. If you can't deal with that, there's nothing I can do about it. ================= Obviously you can't. thanks anyway. I'll wait for somebody else to explain all those other factors someday. Obviously you can't. Mike |
I'm not sure what you mean by "Can the padding be removed from the seat?
I use a rudder if its windy,10 mph or more, otherwise no, don't need it. I think you could get along in the Zoar with a skeg just as well. "donquijote1954" wrote in message oups.com... Bub wrote: Take a long look at the necky Zoar Sport. 14 foot boat w/rudder well made and stable. A little more boat then the Manitou. At $999 w/rudder, its not bad. Bub Thanks! Two questions: Can the padding be removed from the seat? and, Do you get to use the rudder/keg or is it a nuisance? I'll quote something... 'The Zoar Sport is a brilliant little boat. At 14' it is a touring boat rather than a true sea kayak but I have found with mine that: 1) it handles very well on fla****er, keeping close to the longer, "faster" boats; 2) it handles extremely well in surf (force five conditions); 3) it is solid and durable; and above all 4) it is a comfortable fit (I am 6'4" 240 lbs). Great boat.' |
On 17-Jun-2005, Peter wrote: You already provided it yourself. After first making the claim that there was "no correlation" between LOA and LWL, you later provided data indicating that the correlation was 0.79 which clearly showed your initial statement to be false. QED I've already addressed that - the correlation is not sufficient to allow for prediction of performance. You are ignoring that _fact_. As a further indicator of the relevance of LOA as an indicator of performance, let's look at the correlation between the lengths and the drag for the kayaks already presented. Correlation coefficient, LOA vs Drag: -0.35 Correlation coefficient, LWL vs Drag: -0.69 Clearly, an intelligent person would not use LOA as an indicator of performance. This further shows that the correlation between LOA and LWL is insufficiently high. It also shows that other factors beyond just length dictate drag, otherwise the coefficient for LWL vs drag would be higher. For cranky ol' rick, I'll get to other factors later. Mike |
Bub wrote: I'm not sure what you mean by "Can the padding be removed from the seat? I use a rudder if its windy,10 mph or more, otherwise no, don't need it. I think you could get along in the Zoar with a skeg just as well. Thanks. I thought the rudder/skeg may be unnecessary in a kayak of that lenght. I don't like any padding on the seat because of my peeing. Current Designs, for example, doesn't have any. |
Well, settled, I've tried the Manitou and it's too small for me. Later
I tried a Tarpon 160 and found it very nice. It'll be my next boat. THANKS ALL!!! Best Wishes |
Frederick Burroughs wrote: You could have a sharkskin textured slipover designed for your kayak, similar to the swim wear worn by some athletes. In designer colors and patterns, it is worn by your kayak to increase speed and get envious stares. -- "This president has destroyed the country, the economy, the relationship with the rest of the world. He's a monster in the White House. He should resign." - Hunter S. Thompson, speaking to an antiwar audience in 2003. I wouldn't do that. I mean if you are in favor of a democratic world for sardines... "The Forum for Losers.....for those who have no life." I think we kayakers got more in common with sardines. Think about it: WE ALWAYS ARE AT THE BOTTOM OF THE FOOD CHAIN. Yet you see too many sharks around here. They must be trying to stop the little fish from organizing. Well, next time you see one of those fake kayakers out there with the big teeth sticking out, say, "Hey PREDATOR, you are too big for a kayak!" |
...stuff deleted
Lookee, Lookee what I found on the web site that someone posted with Sea Kayaker magazine data: Prijon Calabria Current Design Andromeda LOA 4.42m (14.5ft) 5.26m (17.25ft) LWL 3.96m (13 ft) 4.19m (13.75ft) Drag 16.7 lb 18.0 lb So here we have two _real_ sea kayaks, one that is more than 17 foot long and another that is over 14 feet long (one 19% longer) yet their waterline lengths are 13 and 13.75 feet respectively (one only 6% longer). Note in particular that the _shorter_ kayak has less resistance at 4.5 knots. Mike, This is a pretty good comparison. I assume that the two boats were unladen. Geared up for a long tour, however, the shorter boat should ride deeper in the water (the LWL of the Andromeda should increase significantly as the hull rides deeper), while the Calabria already has most of its hull in the water. One would expect the drag to increase (as well as the beam of the boat) as weight is added. I think this is where we'd begin to see a performance hit on the shorter boat. That is a heck of a lot of hull out of the water on the Andromeda, however. Must be a real joy in wind (though probably pretty fun in surf and waves). Rick |
donquijote1954 wrote:
Frederick Burroughs wrote: You could have a sharkskin textured slipover designed for your kayak, similar to the swim wear worn by some athletes. In designer colors and patterns, it is worn by your kayak to increase speed and get envious stares. I wouldn't do that. I mean if you are in favor of a democratic world for sardines... "The Forum for Losers.....for those who have no life." I think we kayakers got more in common with sardines. Think about it: WE ALWAYS ARE AT THE BOTTOM OF THE FOOD CHAIN. Yet you see too many sharks around here. They must be trying to stop the little fish from organizing. Well, next time you see one of those fake kayakers out there with the big teeth sticking out, say, "Hey PREDATOR, you are too big for a kayak!" The slipover is sharkskin "textured" which results in improved laminar flow, and theoretically less drag. It is essentially hosiery to be worn by the kayak. The fabric can display any design and color you choose, great white, barracuda, guppy, gleeful pink or camouflage... You can even choose a pattern of foam and broken styrofoam, to blend in perfectly with many of today's rivers and beaches. -- "This president has destroyed the country, the economy, the relationship with the rest of the world. He's a monster in the White House. He should resign." - Hunter S. Thompson, speaking to an antiwar audience in 2003. |
On 20-Jun-2005, Rick wrote: Geared up for a long tour, however, the shorter boat should ride deeper in the water (the LWL of the Andromeda should increase significantly as the hull rides deeper), while the Calabria already has most of its hull in the water. Adding 50lb to each kayak only makes the difference in waterline lengths change from 5.8% to 6.2% - not very much. One would expect the drag to increase (as well as the beam of the boat) as weight is added. The Andromeda actual increases its wetted surface more. That is a heck of a lot of hull out of the water on the Andromeda, however. Must be a real joy in wind (though probably pretty fun in surf and waves). I have only paddled the Andromeda for an hour or so in moderate conditions. It sucks. I can't say anything good about that kayak... well, the colour was nice. It's a Derek Hutchinson design. Folks familiar with my opinions on his boat design "skills" will know that I'd expect the results the kayak yeilded. When I talked to Mike Henderson of Current Designs the year before the kayak was sold, he said the kayak in development would be "long and fast" compared to the GulfStream. It is long and slow - much slower than the Gulfstream. How slow? - there are a whole whack of plastic and folding kayaks that are faster. Mike |
Never understood the "TRACKING"" thingy. If the paddler indeed knows how to
"paddle" any boat tracks well. White Water boats are made to spin on a dime, but track as good as anything else if proper paddling strokes are used. "donquijote1954" wrote in message oups.com... That's what I read too. The question is how a recreational boat would be slower than a touring boat of the same lenght. I read a bottom that makes for more initial stability also produces less speed. For example the Biscayne at 14'6" was rated a mere 3 out of 5 in speed when it was a Dagger Savannah... http://www.dagger.com/product.asp?Bo...DC&BoatI D=13 5 Yet it's rated as fast by several reviewers... "Just bought a Savannah Expedition model. Love it -- fast, stable, tracks beautifully. Great fit for me. Paddle some rivers, some lakes, some of Great Lakes. When I demo'd 5 other boats the Savannah was the hands-down winner." http://www.paddling.net/Reviews/show....html?prod=483 |
On Tue, 21 Jun 2005 22:32:07 -0400, "Grip" wrote:
Never understood the "TRACKING"" thingy. If the paddler indeed knows how to "paddle" any boat tracks well. White Water boats are made to spin on a dime, but track as good as anything else if proper paddling strokes are used. Yep. Loaned my buddy my recreational Old Town Otter one day while I paddled my Perception Dancer. He was amazed at how I made it track (and I'm not that good) compared to his friend who'd taken him out one day to paddle ww kayaks on flat water. I explained that I rarely did ww (none by choice any more) and had adapted to paddling flat. He thought I had a different kayak bottom than his friend had. Nope. It is harder to get used to paddling straight in a ww kayak, but not all that bad. And it's great for current and eddy lines in flat rivers. It's not quite as fast going downstream in one, but it's a bit faster going upstream. For me. I'm slow either way. I like to dawdle along slowly anyway. The best part of a keel in flat rivers is that you can do a cross current ferry with almost no paddling going downstream. Cyli r.bc: vixen. Minnow goddess. Speaker to squirrels. Often taunted by trout. Almost entirely harmless. http://www.visi.com/~cyli email: lid (strip the .invalid to email) |
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