Hi Ariel & Captain,
These Ø mm/daN values shown is LIROS website just don't make sense. Sorry if I sounded a bit harsh above
Upto 40% higher breaking strength of SK99 lines vs SK75 lines is realistic, anything above is not. Even if we consider different coating thickness and braiding density/structure. If you have a direct contact with LIROS, ask them to send you the TDS.
For low drag front lines 1.5-1.6mm SK99 is probably the best option, 1.1-1.2mm SK99 for the steering lines. See below actual test data that comes from another European kite lines manufacturer.
Going thinner has few issues:
- SK99 comes only from DSM and in only one yarn count (880 filaments x 1dtex). This means that the final dtex (thickness) of the braided line is limited to 8x880, 12x880, 16x880. With SK75 there are few yarn options that can be used for kite lines. And there are other yarn suppliers of 'SK75 grade' apart from DSM.
- Abrasion resistance of SK99 vs SK75 is likely to be a bit lower (despite being a stronger) as the single filament of SK75 is ~50% thicker than SK99.
- IKA regulations on racing kite lines diameter are: min. 1.2mm front lines and min 0.8mm back lines.
http://sailing.org/tools/documents/FK20 ... 24069].pdf
- Safety - a thin line can cause a much greater damage (cut) if wrapped around any body part.
Another point is the actual elongation (while riding) of the front and rear lines, having different thickness and different load. But I think in foiling this is insignificant and deserves no discussion. Especially with SK99.