mmac wrote: ↑
Sat Jan 12, 2019 5:27 pm
Hmmm, that sounds harsh Matteo. I've been using North/Duotone bars for many years.
This is my experience and the general consensus of every rider I meet who has used, or is using North (now Duotone) lines. They are junk and do not last.
However, I do know what they are going for with these lines. Given the looser, thus lower angle braid, these lines are very thin and strong initially. There is also less material in loose braids there since a tighter braid takes up more length of fibers for a given finished length. Q-powerline has no braid (except the sheath) which gives maximum efficiency and minimum stress due to there being no braid. Technically, these North (now Duotone) lines are higher performance initially. But they do not remain that way.
Sorry I do not have time for a graphic, but I will try to explain.
Given a 6 strand loose braid:
Cut strand # 2 and #5 20cm apart, and the braid does not self tighten (friction) thus you are down to only 4 strands of strength.
Given a 12 strand tight braid:
Cut strand #2, #5, and #8 20cm apart, and the braid self tightens (friction) to make the total strength equal to around 11strands.
This is hard to visualize, but it does give you an explanation why loose braid is the same or better (in Dyneema/Spectra), but only initially. Once wear is factored in, the better line is the tight braid.
I have used 4 North bars, and 3+ Best bars (same line), along with lots of bulk line including Q-Power line. I have used lots of other bars and the North/Best lines are inferior over time, to anything else I have used. Tight braid makes a huge difference. Given that I am 100+kg, I no longer use Best/North lines for front lines where the major load is. Not just for wear, but because stretch is a huge issue at my weight too. I now only use North/Best lines as rear lines. Again, I have a good amount of experience in this in high wear, and low wear kite locations.