Line strength versus Bar strength

A little observation over time, has got me wondering some ???

If the average modern kite line break strength of kites is around 250kg...

Are there any tests on video for actual bar end break strength AND middle bar break strength with a so called 1000kg (+6mm chicken loop line) ???

With all the Major and minor brands going for newer lighter (cheaper?) materials from AsiaLand and some have listed a fault at some stage being bladder or valve / stitching, bar defects or general recals... being caught out by the new materials.

Is the bar that we ultimately trust, in some extreme situations - really up to its job ??

If so can someone post it on here please

Ive recently had a plastic bar end break mid loop upside down - and also someone else with another bar who posted recently too...

But yeah your right - the arms take the load

Back to the original question since its one that should have a REAL answer...

since we get told about "Extra strong kite lines, chicken loops"

Why not the Bars ???

NO NO NO IT CAN AND DOES HAPPEN.
I had a bandit 1 from new and last year the bar broke about a 100mm in during a self rescue ( kite relaunched ( yes i know ) and bust in my hand ) rolled over my 2nd digit and crushed it into 4/5 pieces.
HAD 2 S/STEEL PINS INSERTED IN TO STRAIGHTEN UP MY FINGER.
Fun no and only 95% use back.

Last years F1 bars are ****e,
See this thread
kiteforum.com/viewtopic.php?f=1&t=2374523
Ive also seen a newish nobile bar snap right in the middle.

... I bent a bar just moments before the lines snapped, downlooping in 30 knots or so!

I was out riding with the missus, she was on a 14m, me on a 16m. The wind picked up so we put down, and I grabbed her kite. Her bar and lines were new, used first time. During a downloop gybe, dug the heals in and as kite was racing across the wind window, an almighty pull then twang, snapped both steering lines! Later on I noticed the bar was bent, not by much but all the same bent, roughly 5 or 10 degrees from memeory. I got in so much trouble, I had to buy her a new bar. I've still got it somewhere, I'll try and get a pic.

Would love to know what pressures were involved.

cheers,

Robbie

ps kite did fold and jelly, no wonder with all that pressure.

Naish use Carbon fibre bars, with a cast aluminium centre hole. The problem with CF is that it while does well reducing vibration but doesn't take hard knocks. And when it fails, it snaps, rather than bending or progressively cracking. Aluminium alloys is fairly similar in this respect.

The reality is that breakages will happen in extreme circumstances, even if the bar is well over specced for the job.

All you can do is make sure you don't drop your bar on hard surfaces/ or mishandle it. Check the bar wrap/grip for gouges and scratches that may have occurred through into the bar itself. Deep scratches are the enemy of carbon fibre.

I ride a carbon fork and tail bike and I probably put more stress on the bike frame than I would a kite bar. You hear of carbon forks and frames failing but in most cases it's because the owner drove into the garage without taking the bike off the roof rack!

all of the carbon gear is engineered to take a specific load that would be pre designed by an engineer, and then tested to breaking point. and like all things they would be over engineered to take a screw up but designed to be used in a certain way,,,digging heels in the sand and looping i would highly doubt would be a "normal" condition that the bar would be designed for. I have sail 18ft skiffs with the class builder in San Fran in 30knts and although he builds and does the design work was worried when going downhill and absolutely smoking( he was crapping himself well we all were) saying the loads we were putting on the boat were way over what they are designed and engineered for and since he has gone back and added strength where needed, they wont always get it right but like any extreme gear you have to expect some breakages when your doing your thing! i kite loop in 30 is hectic!