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I need convincing too:) Bar back lines!

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Matteo V
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Re: I need convincing too:) Bar back lines!

Postby Matteo V » Mon Apr 23, 2018 3:36 am

downunder wrote:
Mon Apr 23, 2018 2:41 am
Depending on the location, one might never need thick lines. Also, the back lines are quite thick near the bar for holding, so not a problem for the rider.
It is becoming evident that you may be one of those people that needs to learn by experience, not advice. Your initial and further questions have been answered and to recap:

Minimum thickness back lines are for -
Handling safety
Wear safety
Connection safety
Loading when the kite wraps a bridal
Unhooking loads
The danger that breaking 1 back line presents (uncontrolled looping)


downunder wrote:
Mon Apr 23, 2018 2:41 am
Sure, a super thin lines can do a lot of damages but we need to put this into perspective of the sport.
The perspective has been established by the kite community long before I even became part of it. And it has evolved since then to the point where racers are not dropping below a certain minimum. Ozone has a pretty well established floor on the back line strength at 200kg. Given that racers are looking for every advantage, but are stuck with the reality of diminishing returns, your answer is right in front of you.

If you want to repeat others experiments below this threshold, go ahead and make sure to report back. But please be careful and respectful of other kiters. When your 100kg lines snap after 10 sessions, try to make sure you have your issues away from other kiters and especially innocent beach goers.

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cglazier
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Re: I need convincing too:) Bar back lines!

Postby cglazier » Mon Apr 23, 2018 3:37 am

Over the years the big kite manufacturers have determined what kite line strength is appropriate for normal use for average weight riders. It is always a trade off between durability and strength versus performance. You can buy race line sets from companies like Ozone which are thinner and have less strength.. and they seem to work most of the time. (Note that Ozone also uses stronger lines for the fronts than the rears.) I have set of these race lines that I got for racing but I never use them for recreational kiting.. the small improvement in performance (reduced drag) is not generally worth the risks in my opinion.

But if you are very light weight and you don't mind using rather sharp lines that are fragile you can give them a try.

:-) CG

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Re: I need convincing too:) Bar back lines!

Postby jakemoore » Mon Apr 23, 2018 4:34 am

downunder wrote:
Mon Apr 23, 2018 2:54 am
Don't really see relevance in questions? :) The bar pressure is irrelevant coz at this stage we have no clue what bar pressure is translating to. It's just a 'guesstimate', no real data exist. Or does it.
You can get a reasonable upper bound on the bar pressure and rear line tension through guesstimate. If you can't do a one armed pull up but you can pull the bar to the chicken loop, then the rear line tension is less than your body weight divided (unevenly at times) between the two rear lines. So my point is if your kite has lower bar pressure like a foil kite and you are not trying to use your snow-kite as a paraglider than maybe thinner back lines make sense. Yes bladders, canopies, bars and harness can fail just as lines do. A conversation about shaving whales off of kite lines deserve a mention of how much risk. My light wind riding is low risk and I like my thin lines. I would not want to recommend thin lines to somebody and have them fall.

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downunder
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Re: I need convincing too:) Bar back lines!

Postby downunder » Mon Apr 23, 2018 4:52 am

cglazier wrote:
Mon Apr 23, 2018 3:37 am
Over the years the big kite manufacturers have determined what kite line strength is appropriate for normal use for average weight riders. It is always a trade off between durability and strength versus performance. You can buy race line sets from companies like Ozone which are thinner and have less strength.. and they seem to work most of the time. (Note that Ozone also uses stronger lines for the fronts than the rears.) I have set of these race lines that I got for racing but I never use them for recreational kiting.. the small improvement in performance (reduced drag) is not generally worth the risks in my opinion.

But if you are very light weight and you don't mind using rather sharp lines that are fragile you can give them a try.

:-) CG
:)
I am jumping ~10m with super thin race lines for the last n years. I'm 59kg and can assure you, they are not fragile as the general community might think. The risk is why they fry. So don't fry it.

The FS back and front lines are super thin.

Still not convinced about how much we pull.

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downunder
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Re: I need convincing too:) Bar back lines!

Postby downunder » Mon Apr 23, 2018 5:25 am

Matteo V wrote:
Mon Apr 23, 2018 3:36 am
downunder wrote:
Mon Apr 23, 2018 2:41 am
Depending on the location, one might never need thick lines. Also, the back lines are quite thick near the bar for holding, so not a problem for the rider.
It is becoming evident that you may be one of those people that needs to learn by experience, not advice. Your initial and further questions have been answered and to recap:

Minimum thickness back lines are for -
Handling safety
Wear safety
Connection safety
Loading when the kite wraps a bridal
Unhooking loads
The danger that breaking 1 back line presents (uncontrolled looping)


downunder wrote:
Mon Apr 23, 2018 2:41 am
Sure, a super thin lines can do a lot of damages but we need to put this into perspective of the sport.
The perspective has been established by the kite community long before I even became part of it. And it has evolved since then to the point where racers are not dropping below a certain minimum. Ozone has a pretty well established floor on the back line strength at 200kg. Given that racers are looking for every advantage, but are stuck with the reality of diminishing returns, your answer is right in front of you.

If you want to repeat others experiments below this threshold, go ahead and make sure to report back. But please be careful and respectful of other kiters. When your 100kg lines snap after 10 sessions, try to make sure you have your issues away from other kiters and especially innocent beach goers.
Matteo, ummm, answered by what? 5%? With due respect, but how did 5% come into equation? Why not 7%? or 9? 12?

Put it this way, please go into the shop and buy the bar for 50kg rider. Can you do that by your experience? No? So how come I can buy a KITE to suits all weights? Ahh, I know, because it's easier to sell the kite but not the bar with lines for specific weight.


Let's recap with my critique:

Minimum thickness back lines are for -

Handling safety - you mean releasing safety? How are back lines involved? Sure, I've released a number of times and towed the kite on one thin line.
Wear safety - wear? Replace them then. Do you replace bladders every now and then? No? Well than...
Connection safety - connection to what? Bar/kite? Cmon, pigtails are used for that or whatever.
Loading when the kite wraps a bridal - Sure, any line can fry under some circumstances.
Unhooking loads - do you unhook? 99% do not unhook intentionally. Unintentional unhooking does not count.
The danger that breaking 1 back line presents (uncontrolled looping) - any line can break.

Now my turn:

- easier to sell one bar
- cheaper to have one supplier
- cheaper to test or
- near impossible to test, hence
- blanket rule
- herd mentality (how many u know running any non stock lines?)

And not talking racers at all.


When your 100kg lines snap after 10 sessions, try to make sure you have your issues away from other kiters and especially innocent beach goers.
Gee, assumption is a mother of all ...You do not know me and my local conditions so stop and think before assuming. Thanks :)
Last edited by downunder on Mon Apr 23, 2018 5:30 am, edited 1 time in total.

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downunder
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Re: I need convincing too:) Bar back lines!

Postby downunder » Mon Apr 23, 2018 6:23 am

jakemoore wrote:
Mon Apr 23, 2018 4:34 am
downunder wrote:
Mon Apr 23, 2018 2:54 am
Don't really see relevance in questions? :) The bar pressure is irrelevant coz at this stage we have no clue what bar pressure is translating to. It's just a 'guesstimate', no real data exist. Or does it.
You can get a reasonable upper bound on the bar pressure and rear line tension through guesstimate. If you can't do a one armed pull up but you can pull the bar to the chicken loop, then the rear line tension is less than your body weight divided (unevenly at times) between the two rear lines. So my point is if your kite has lower bar pressure like a foil kite and you are not trying to use your snow-kite as a paraglider than maybe thinner back lines make sense. Yes bladders, canopies, bars and harness can fail just as lines do. A conversation about shaving whales off of kite lines deserve a mention of how much risk. My light wind riding is low risk and I like my thin lines. I would not want to recommend thin lines to somebody and have them fall.
Fair answer.

Sure, you're right, it's 5% (assumption, no data exist), between TWO lines, hence 2.5kg max per line for ~100kg rider. But, again, it is an assumption with no real data to support it. So how can we design something based on fictitious data?

Particularly when we jump? I would argue that at the moment of jump the lines tension increases but how much? Double? So, 5kg each.


~

I am totally the opposite, I jump, do tricks, all with one bar between 4 kites. And the bar is with the custom race lines and 200-300 hours on it. Never going out when nuclear wind, max to 27-30kn. I was out on a number of occasions with 35kn gust tho. Nothing happened. Seen heaps standard stock lines broken.

The lines did not shrink/expand at all that I've noticed. Running bar lines length test every 6 months. So if the lines are intact in length after that many hours, where is basis of running thicker lines because they change less in length? Ffs, are you using your lines for 5 seasons? God, that's risky if doing 200hrs/season (this is not to you jake...).

~

This post was inspired by "Kite manufacturing - free feedback", and as such it questions the design and offer/purchase choices.

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downunder
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Re: I need convincing too:) Bar back lines!

Postby downunder » Mon Apr 23, 2018 6:37 am

Matteo V wrote:
Mon Apr 23, 2018 3:36 am
.
.
The perspective has been established by the kite community long before I even became part of it. And it has evolved since then to the point where racers are not dropping below a certain minimum. Ozone has a pretty well established floor on the back line strength at 200kg.
.
.
God, took me 5 seconds (less since I'm using this lines anyway):

https://flysurfer.com/project/race-bar-pro/

"For the Race flying lines, we have worked to find an optimal balance between diameter reduction and breaking load (front 1.45mm / 300kg – Back 0.8mm / 160kg)."


How about that Mr kiting Authority? ;) Joking, you are not mate. You're trying to be one tho, however the FS is discrediting you. Not me.

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Re: I need convincing too:) Bar back lines!

Postby evan » Mon Apr 23, 2018 7:08 am

Ha, line strength. If you only fly the kite with no power spikes you can get away with really really thin back lines. Sadly we have to deal with gusts, kites falling and repowering after you made a mistake where you can get enough power on a single line to snap even a 300kg rated line.

Tested used and new lines for my line repair company of multiple brands and it is really shocking how some manage to f*** up the strength by their cheap manufacturing or rapid deterioration of the line.

For example North lines with the shrink wrap around the sleeve ends that eats into their already fast deteriorating lines (getting fluffy way faster than other brands). Breaking loads of a year used line set did go as low as 120kg because the line frayed away just behind the sleeve. No wonder you brake all four lines in a cascade effect when the power lines fail...

And don't get me started about the elasticity of naish lines :)

Evan - Infexion bar and line repair

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downunder
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Re: I need convincing too:) Bar back lines!

Postby downunder » Mon Apr 23, 2018 7:26 am

Nice.

Of course, all of the above happened to many times to remember.

Refreshing post. Thanks!

Matteo V
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Re: I need convincing too:) Bar back lines!

Postby Matteo V » Mon Apr 23, 2018 3:07 pm

downunder wrote:
Mon Apr 23, 2018 6:37 am
God, took me 5 seconds (less since I'm using this lines anyway):

https://flysurfer.com/project/race-bar-pro/

"For the Race flying lines, we have worked to find an optimal balance between diameter reduction and breaking load (front 1.45mm / 300kg – Back 0.8mm / 160kg)."

How about that Mr kiting Authority? ;) Joking, you are not mate. You're trying to be one tho, however the FS is discrediting you. Not me.
I bet you missed this part from Flysurfers bar description in that exact link, especially if you only took 5 seconds to look at the number and you did not read the description.

"This Bar setup is intended for Racing only and is not suitable for jumping!" - from the link you posted

Do you jump? (I feel for you I should note that this is a rhetorical question as I have read the above posts. You seem to take things a bit literally)


In your rage to frame me as a "Mr. knowitall", you have again demonstrated your inability to see what is right in front of you. The lower limit has been established, though it is not solid number. At 160kg, you are definitely good to go with regular replacement of the lines and NO JUMPING. At 200kg, you are recommended to replace after 100hrs and still shy away from high loading, definitely no wakestyle or beginner usage/crashes. For regular kiteboarding usage, jumping, trying new things that result in crashes, and long wear life, go up to 250-300kg minimum on you back lines. I am afraid more clarity on this issue is not possible.

I am not trying to berate you because I very much appreciate your post. It adds discussion and gives kiters an idea of the mentalities/ideas out there. So thanks and keep posting.
Last edited by Matteo V on Mon Apr 23, 2018 4:03 pm, edited 2 times in total.


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