Ok through the process of elimination, it appears my kite must be twisted. Cannot see it visibly though.
Have meticulously measured all bridle lines, kite lines front and back. All are symmetrical and even length. So can only assume the uneven bar pressure (quick steer on one side slow steer opposite side) is due to a twisted leading edge bladder,
as was suggested.
Does the bladder have to be taken out and put back in again to remove the twist?
Is there an easier way?
If it's a twisted bladder you should be able to see it when the kite is inflated look over the leading edge to find it then deflate the kite open the leading edge tail of the end which has the twist and leave it hanging out go to the center of the kite and start shaking the leading edge fairly hard work your way down to the tail shaking the crap out of the leading edge about 300mm at a time to you get to the tail put the bladder back in the tail cover re inflate the kite should be good to go if not keep repeating this process you will get it .
What kind of kite, if it is a 1 pump it is very unlikely to be twisted. Good luck whatever it is
If your kite has pulleys in the bridal try putting new ones on . One of my old kites started turning funny found out one of the pulleys was worn out put some new ones on made a big difference .
Ah - the mysterious turning kite...
I'm assuming your kite is not brand new, because if it is back to the retailer!
Check your bridles are all the same length, flying lines stretch out evenly, and pulleys run freely.
If it's not the above then it may be the bladder, but you should be able to see the kite sitting unevenly when you pump it up.
It is pretty unusual to get a bladder twist without having taken the bladder out (for example to repair something).
Last check is stretched fabric, but the kite will usually be very used and abused to have that problem.
Have you tried connecting steering lines to oposite sides? ie red to white?
Try someone elses bar and lines
Does that mean you havent checked your line lengths. I bet you its a front that is not quite right.
Geeze you are one tolerant character ! after all of the Q's you have been asking and still not biting on some of the interesting answers !! thumbs up buddy!!
I still have no idea what is causing your problem (other than its a north kite) so I'm watching to see what is the best solution to your problem.
Galah said to do as you have already done - Next ??
Stuntnaz has a point - you should be able to 'see' a leading edge bladder twist - may be not??
Ok so this is nuts but what does North (your local distributor) have to say about your dilema ??.
It shouldnt be too hard to pull out your leading edge bladder and then slide it back in - but I have to say thats a job I'd prefer to avoid - if it anit broken why try to fix it! ha ha
I had two or three kites like that way back at least 8 years ago. As they were new, I could take them back to the retailer after a "credible" guy double checked everything.... and found nothing wrong with the lines etc., so it was a manufacturing fault...
Some explanations:
Oder kites canopy may stretch differently on the two sides.
There is a manufacturing error (stiching, cutting etc). It doesn't have to be visible to be significant.
The leading edge itself (not the bladder) may be just a bit twisted... again, you wont see it only feel it when flying the kite.
So, if it is an old kite, or newer but had its time, retire it. If it is a new kite, take it back to the retailer.
try inflating the kite fully,
place it on a flat even surface and look at it from behind.
check to make sure the kite is symmetrical, look for signs, like one wing tip may not be touching the ground or pointing outwards more than the other.
It has been known for segments of kites to be stitched together incorrectly.
hopefully all is good.
When checking your bar line lengths - did you check it "under tension" ???
Not just side by side etc - you will miss a soft/faulty line if that is the cause.. ?
Its all good folks. I reversed the bar today and the problem disappeared.
So one of my bar lines has stretched an infinitesimal amount, barely noticeable at the bar. More noticeable in flight while steering. Easy fix...buy new lines.
Thanks to all those who gave constructive advice.
Ues a shackle and attach the loops on the end of your lines, attach to something solid. Power up the bar with the trim line and the bar should be at the chicken loop. PULL hard. North lines around 320 coins
i know alot of people have had issues with their kites turning one way, and its the stitching coming loose or the different coloured fabrics reacting to the sun differently. With the new vegas heaps of people have had this issue with kites pulling one way, i know someone who has been thru 5 12m vegas 2013's already coz they keep pulling one way.....
maybe check all of you stitching to see if its all holding up well, if its your lines its an easy fix, just tie them up, but its most likely the kite if u cant seem to fix it, which in most cases makes it unfixable
Hey dorothy
Good to hear youve figured it ... eventually 
Now for your next lesson 
when you fit the new lines... you Must check them under full bodyweight Tension. If not sure then get someone to show you..
Never take for granted that anything on kites n bars from a mass production factory is set properly - check over everything before and after your first session !
The bar n lines should always be your first checkpoint... and rechecked every few months
Why dont you just ride with your lines back to front? If you keep stretching them lines its going to have an effect on the amount you can/cant trim your kite.
If kite fabric has stetched like Ewan said then line replacement might only be a short term fix.
Trade it in for a BWS!
