Here’s how to make the shorter bridle mod.
Materials Needed :
4 pulleys : Ronstan RF 13101-2 kite blocks ( http://www.ronstan.com/marine/product.asp?ProdNo=RF13101-2 ) - will cost between $5 - 10 US each.
V-lines : Several meters of Samson rope 7/64 inch diameter Amsteel Blue line ( http://www.samsonrope.com/index.cfm?ind=1&app=3&rope=192&inst=1 ). See the chart below for the total lengths needed for various kite sizes. You can use the factory bridle H line, but if it’s severely worn where it ran through the pulley on the kite, I wouldn’t use that section. Cost is from about $0.30 - $1.00 / ft.
Pulley pigtails : ~ 1 meter of double-braided Spectra or Dyneema cored & polyester sheathed 2 or 3 mm diameter. I used Marlow Excel Racing ( http://www.marlowropes.com/public/pageManager.cfm?page_id=161 ) New England Rope Spyderline ( http://www.neropes.com/product.aspx?mid=FBAE29336C3B26FE710A6F20A0FF186C&lid=3&pid=201 ) should work, or even the 7/16 Amsteel if you can’t get hold of some thin double-braid line - cost about $3.
Sources for these materials range from your local kiteshop, marine store ( especially one that supplies small boat / dinghy sailing tackle ), or online. There are good prices for this stuff online, but shipping and handling costs can be significant.
Here are the V-line lengths for all kite sizes.
Remove kite bridle lines H, I, G, and E. Your commitment to this mod will determine your method of removing H. If you want to be able to go back to the factory bridle, then mark on H line where the two Figure-8 knots are just above the rear attachment loop and un-tie them, and pull the H line through the pulley on the kite. Untying these knots won’t be easy, but the knots on the front line end of H are tighter and there are more of them. Use an awl to “spike” the knot several times to loosen it up. Far easier, provided you are committed, is to either cut the Riley pulley off the kite, or cut the H line at one end.
Install the G bridle line at the kite wingtip. This line will attach directly to the kook-proof leader on your steering line, just like on the Rise.
Cut the required length for a V1 line ( see the cut lengths in the table above – note that an 8-knot takes up about 4.5 cm of line ). Tie a Figure-8 knot at one end, thread a pulley onto the V-line, and tie a second 8-knot the appropriate distance from the first knot ( see the knot-knot lengths on the chart ). Connect the C and D bridle lines to either end of the V1 line with larks-head knots. Using 15 – 18 cm of line, tie a pigtail onto the pulley. Attach the I bridle line to the pulley’s pigtail. It should look like this :
Make up a V2 line, with two additional knots spaced 3 cm apart at one end. These extra knots are for tuning the kite, more about them later. Attach the free end of I bridle line to the single-knot end of the V2 line. Install the E bridle line onto the former pulley attachment point on the kite. Larkhead the free ends of lines F and E to the innermost knot on the V2 line. It should look like this ( note - 3 adjustment knots are shown in this pic, but I doubt you will want/need this much adjustment, maybe on a 16m ? )
Attach a pigtail to the pulley on the V2 line. If using 2 mm diameter line, double it up for added strength and safety, as OR does on the Rise. Attach your front flying line to this pigtail’s knot.
Laying your kite flat, with the bridle lines extended back as in the picture of half the kite above, the wingtip bridle line ( G ) should extend 2 – 3 inches past the end of the pigtail on the V2 line.
Now do the other side. Regarding line lengths, my table of lengths shows measurements to the millimeter, but you don’t have to be that accurate, just make the knot-to-knot lengths similar on both sides of the kite, within a millimetre or two.
Test fly your kite on a mellow day and safe spot. Before you launch it, pull in your trim line 4 or 5 inches, just to be safe. If it flys well, then grab a big board and try it out on the water. With E and F lines at the first knot, the bar loads should be light. Kite stability should be great, even with the kite sheeted out a long way – no more front stalls when heavily sheeted out. De-power should still be abundant, but a little less than the factory bridle. If you want more bar load and de-power, then move the E line out a knot or two. If your kite doesn’t backstall with the trim line all the way out, the bar at the chicken loop, and the kite deep in the power zone, and you want more power from the kite, lengthen the V2-line by moving both F & E out to the last knot. If your kite backstalls too frequently, and your bar’s front and rear flying lines are equal in length, then shorten the V2 lines. When you’re happy with the kite set-up, cut off the excess on the V2 lines not being used, as I’ve done on my 9m.
I will post again the methods I used to scale the bridle down for 7m and up for 12 and 16.