Unibladder kite upgrade

I got a new 9 meter inflatable kite recently, for kiteboarding.

I tried it out in the snow a couple of weeks ago and found that the stopper balls weren't working in the outside struts.  Without the stopper balls, the outside struts could not be inflated enough to give the kite decent shape.

The kite was of the type where each strut and bladder has its own valve.  To fix the problem with the outside struts I decided to convert the kite to having only one inflation valve, with a system of tubing (clear plastic vinyl) that runs to each of the other valves.

The kite valves are typically 9mm inner diameter (ID).  for the conversion I used plastic barb fittings with 3/8" outer diameter (OD) (in USA so 3/8" easy to find).  3/8" is 0.375 inches and 9mm is about 0.360 inches so the larger barb had to stretch the 9mm valve at least 0.015 inches and this gave it a good snug fit with no need for a hose clamp.  I used a hair dryer to warm it up before cramming the barb in with my hands (tools might rip or break the kite so I used my hands only).

The tubing I used was 5/16" ID, with 3/32" wall. I tested that tube, and a thicker 1/8 wall tube in the freezer and both survived bite tests at cold temp.  I used the thinner because it weighs less.

Since the 5/16" tube is much smaller than the 3/8" barb, it needed to be warmed with the hair dryer and then really crammed in.

For the outside struts I used right angle barb fittings, for the inside struts, middle, and leading edge bladder I used Tee barb fittings.

On the leading edge I have a Tee with one side pointing up, and to that I connect a special-ordered 9mm ID tube.  I tried 3/8 tube there but it would leak a bit when it moved.  5/16 was too small to fit the 9mm cap into if one were out in the snow and wind with cold hands.  This part is where the pump can be inserted to inflate the entire system.

It works like a charm, and after pulling the pump the entire system stays well inflated while I seal it with the cap.  The kite now has really nice shape.

Pictures to come.
included are some photos of a similar project I did on a 7m C-kite Naish.