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Re: New Milestone in Kitesports Safety: ISO Standard 21853 on Quick-Release Systems

Posted: Fri Apr 10, 2020 10:42 pm
by a99
6 years takes to get to one release standart, which by the way so simple in desciption and technicaly so easy. Takes 6 next years for color standart iso on bar :) :) very big question red on left or not and stop on back side or not:) very fast progress definitely:)

Re: New Milestone in Kitesports Safety: ISO Standard 21853 on Quick-Release Systems

Posted: Fri Apr 10, 2020 10:56 pm
by knotwindy
I had a bar that was slightly oblong/out of round so as soon as you grabbed it you knew by how it fit in your fingers whether it was right way or backwards without even looking at all. Really worked well & I liked it a lot. Also, made just holding the bar while riding more comfortable. Anyone else tried this?

Re: New Milestone in Kitesports Safety: ISO Standard 21853 on Quick-Release Systems

Posted: Fri Apr 10, 2020 11:46 pm
by BenBen
Yeah, Airush had a rubber covering on their bars which fitted to your hand / fingers. When you turned it you had the finger imprint on your hand side and could feel that there s something wrong. It worked somehow. But I didn't liked the feel. Maybe having a slightly out of round bar would be the better way.

Re: New Milestone in Kitesports Safety: ISO Standard 21853 on Quick-Release Systems

Posted: Sat Apr 11, 2020 1:14 am
by purdyd
knotwindy wrote:
Fri Apr 10, 2020 10:56 pm
I had a bar that was slightly oblong/out of round so as soon as you grabbed it you knew by how it fit in your fingers whether it was right way or backwards without even looking at all. Really worked well & I liked it a lot. Also, made just holding the bar while riding more comfortable. Anyone else tried this?
I think it is a good idea and I’ve used bars like that. But there are times if you grab the bar wrong and then feel it is backwards, it is too late.

Like un spinning the bar on a small kite.

Re: New Milestone in Kitesports Safety: ISO Standard 21853 on Quick-Release Systems

Posted: Sat Apr 11, 2020 1:44 am
by knotwindy
Could happen I guess but I don’t remember that ever happening to me. Could just be my memory though!
Most of the time if I grab the wrong side on a smaller kite I just pull harder and tight loop it. Usually works very nicely but not 100% sadly.
But I suppose we’re off topic about regulations. Sorry.

Re: New Milestone in Kitesports Safety: ISO Standard 21853 on Quick-Release Systems

Posted: Sat Apr 11, 2020 4:39 pm
by sq225917
I prefer a bar that feels back to front, it can have a ridge, dot pattern, whatever. That way i know my bar is flipped without having to take my eyes off the kite.

Re: New Milestone in Kitesports Safety: ISO Standard 21853 on Quick-Release Systems

Posted: Sat Apr 11, 2020 4:41 pm
by sq225917
decay wrote:
Thu Apr 09, 2020 8:03 pm
sq225917 wrote:
Thu Apr 09, 2020 6:29 pm
Until someone has run back to back tests on the same units under both regimes its impossible to say if they are comparible or not.
I personally have, hundreds of tests on both setups using a vast range of QRs.

I designed, built and qualified the system the standard is based on.

Cheers

DK
That much was obvious from yuor first posts Dave.


So having done hundreds of tests, you must have an idea is 15 is less than 17?

Re: New Milestone in Kitesports Safety: ISO Standard 21853 on Quick-Release Systems

Posted: Sat Apr 11, 2020 5:18 pm
by purdyd
sq225917 wrote:
Sat Apr 11, 2020 4:41 pm
decay wrote:
Thu Apr 09, 2020 8:03 pm
sq225917 wrote:
Thu Apr 09, 2020 6:29 pm
Until someone has run back to back tests on the same units under both regimes its impossible to say if they are comparible or not.
I personally have, hundreds of tests on both setups using a vast range of QRs.

I designed, built and qualified the system the standard is based on.

Cheers

DK
That much was obvious from yuor first posts Dave.


So having done hundreds of tests, you must have an idea is 15 is less than 17?
I thought this was clear?
The actuation and force measurement systems are considerably different between ISO 21853 and AFNOR meaning the pass/fail load limits are not directly comparable.

Re: New Milestone in Kitesports Safety: ISO Standard 21853 on Quick-Release Systems

Posted: Sun Apr 12, 2020 7:28 pm
by sq225917
I think that's as clear as mud, pure obscurification. Especially if he's done 'hundreds of tests'.

You take as many Afnor designed bars and as many ISO designed bars as you can find and you test them all under both testing standards. Then you crunch the results to see if there's a correlation between Afnor and ISO bars with regards to lowest release force. It's a moderate statistical challenge to find the standard deviation for each regime and pronounce a winner.

Having read the specs I'll settle for my initial presumption.

Re: New Milestone in Kitesports Safety: ISO Standard 21853 on Quick-Release Systems

Posted: Sun Apr 12, 2020 7:52 pm
by purdyd
sq225917 wrote:
Sun Apr 12, 2020 7:28 pm
I think that's as clear as mud, pure obscurification. Especially if he's done 'hundreds of tests'.

You take as many Afnor designed bars and as many ISO designed bars as you can find and you test them all under both testing standards. Then you crunch the results to see if there's a correlation between Afnor and ISO bars with regards to lowest release force. It's a moderate statistical challenge to find the standard deviation for each regime and pronounce a winner.

Having read the specs I'll settle for my initial presumption.
That could certainly be done and likely has been.
ISO21853 is by no means easy (or easier than AFNOR) to pass,
I think your question was unclear, but you did clarify what you were asking for.

I agree I would like to see more transparency on this. One of the problems with iso standards is getting ahold of them.

It is not clear on how they arrived at that number. Presumably some testing rationale.

Decay Obviously has a test bench it would be nice to see a video and results of running a quick release through the tests.
sets the standard for maximum release force (equal to or less than 170N) and opening time (equal to or less than 2 seconds) of quick-release systems under different standardized conditions like
water with and without sand
dry and clean conditions
dry sand
cold and wet conditions
So about 20 Newton’s or roughly 2 kg difference but I’m not sure of the load,