Trimming
and Tuning
It is important to trim your kite to ensure that the kite is safe and
fly's efficiently. Kites are trimmed to achieve the correct amount of
power the rider desires. We can also tune a kite to fly either faster or
slower. There are lots of different kites and they all have different
aerodynamic characteristics and therefore have different tuning
techniques and effect.
Tune the kite to turn slower:
1. While learning
2. In very strong wind if the kite is too nervous
Tune the kite to fly slower:
1. While learning
2. In very strong wind
Tune the kite to turn faster:
1. In light wind
2. When using a shorter control bar
Tune the kite to fly faster
1. In light wind
2. If you prefer to use longer lines (40 m)
Tune the kite to resist luffing and nose diving
1. In gusty wind
2 Line Inflatable
2 line inflatable kites can be tuned to turn faster by tighten up the
bridle and turn slower by loosen up the bridle. Using a longer bar can
also turn the kite faster and a shorter bar slower.
4 Line Inflatable
Most modern 4 line inflatables have multiple connection points (usually
2) for the the front lines and back lines.
* Use the "front most" front attachment for more depowering capability
* Use the "back most" front attachment for more power on the harness
line (chicken loop line)
* Use the "back most" back attachment for fast turning of the kite
* Use the "front most" back attachment for slow turning of the kite
Overall, use the connection points further apart for more control and
wider wind range. Use the connection points closer together for more
stability and lesser bar sensitivity.
2 Line Control Bar
If you are using a 2 line control bar, you have to select the right
length of the bar for the kite you are using. Use shorter control bar
for smaller kite and longer control bar for larger kite. You should be
able to find the optimum lengths for all of your kite after a number of
trials. As a general rule-of-thumb, if your kite is too nervous, use a
shorter bar and if your kite is too slow to react to your command, use a
longer bar.
4 Line Control Bar
If you are using a 4-line inflatable, you can tune the angle of attack
of the kite by shorten or lengthen the front leader line. Less angle of
attack means less pull and the kite flies faster; however it's slightly
harder to turn the kite. More angle of attack means more pull and the
kite flies slightly slower. You should tune the neutral angle of attack
of the kite such that when the kite is flying straight above, the back
line will get loose when you hooking in to the chicken loop and fully
extending your arms (your hands are holding the control bar). Both front
lines and back lines should be in full tension when you are not hooking
in the chicken loop and the kite should be a bit "flared out" (the front
leading edge looks larger than the trailing edge). You can adjust the
AOA of the kite using the chicken loop or via a trim strap.
Foils
Most 3 line foils have both of the front lines attached to the ends of
the bar and the brake lines attached to the center of the bar. Such
arrangement normally need a power steering line that attaches each front
line to its corresponding trailing edge. By tuning this power steering
line properly (when the kite is flying straight overhead, the power
steering line should have no tension nor slack), the kite can be made "unluffable"
even in very gusty wind (the power steering lines are acting as an
"automatic" brake to prevent the kite from overflying).
If you are using a ram air foil kite with a pair of 4 line handles, you
can tune the "camber" of the kite while you hold the handles in their
neutral position (the "neutral camber"). You can decrease the neutral
camber by connecting the main lines to the closer knots and back lines
to the farther knots on the lines that attached to the handles. You can
increase such camber by connecting the main lines to the farther knots
and the back lines to the closer knots on the lines attached to the
handles. You should tune the neutral camber of your 4 line kite such
that when you hold the handles in their neutral position, the kite
should fly forward with full power - the front lines are in full tension
and the brake-line is slightly loose. Increasing the neutral camber will
make the kite generate more pull.
For the new generation of foils using 3 line with a bar such as the
Concept Air New Wave, you can change the "camber" of the kite by
adjusting a strap while sailing thus change the characteristics of the
kite. Such arrangement increases the wind range of the kite. Some newer
generation of foil such as the Jojo Rage can have an optional 4th line
which one can be adjusted to change the shape of the kite (neutralize
the middle section) to reduce the pull of the kite.
You can also use a foil/sled depowering system that can turn a foil into
a sled. More information about the foil/sled depowering system can be
found in the Tips section. Similar to inflatable, modern foils have the
ability to change its AOA, thus use the same control bar as 4 line
inflatable and require similar tuning.
Lines
You can use longer or shorter line length. Use the following general
guidelines to select the right line length:
Use longer lines (40m - 45m):
1. If the wind is light
2. If the wind is gusty (with smaller kite)
Use average lines (25m - 30m)
1. For most condition
Use shorter lines (15m - 25m)
1. If the wind is strong
2. If you kitesurf in wave
Using different line length increases the wind range of your kite. The
standard line length is 25m - 30m as such line length is best for
all-around kitesurfing (going upwind, jumping, moving the kite to
generate more power, etc.). By using 15m lines, you can add another 10 -
20% to the upper wind range of the kite and by using 45m lines, you can
add another 10 - 20% to the lower wind range of the kite. So be
adventurous and use different line length with your kites. The only
disadvantage of using too short lines (15m) or too long lines (45m) is
that it would make jumping harder as you have to change the timing you
normally use with 25m - 30m line (also jumping with 15m line is
difficult as it's hard to generate enough power to lift you up using
such a short line).
Line strength used is actually a function of your weight. The lines in a
2-line kite should have a minimum strength equals to 2.5 times your
weight. For a 4-line foil, the main lines should have the minimum
strength equal to 2 times your weight while the brake lines should have
the minimum strength equal to your weight. For example, if you weights
200 lb., you should use at least 500 lb. lines for your 2 line kites and
400 lb. main lines, 200 lb. brake lines for your 4 line kites. For a
4-line inflatable, all the lines should have a minimum strength equals
to 2.5 times your weight.
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