There are 2 types of depower systems for kitesurfing control bars; The Above-the- Bar and Below-theBar. The picture to the right has shots of both above and below depower systems from different manufacturers:
Trimming allows you to change the power of the kite. Your trim strap (shown below) can be adjusted to either give the kite more or less power, depending on how you set it. It’s located near the bar and is always within reach when you are riding.
As you can see, every brand has a different style of trim strap, but in the end they all work the same.
Sheeting allows you to adjust the kite’s power by moving the bar relative to you, but trimming changes the overall amount of power that you get at the bar. It’s meant to tune your kite exactly to your riding preference and the current conditions.
Example – You launch your kite and are feeling the amount of power it has in the wind. You have too much power so you sheet out – but sheeting out that far puts you into an uncomfortable position. So, you grab the ‘depower’ line on the trim strap and use it to depower the kite until your preferred bar position is the most comfortable.
But then, after 30 minutes on the water, the wind dies down a little. You sheet in all the way, but you don’t have enough power – so you grab the ‘power’ line on your trim strap and pull until your kite has enough power to ride.
Note – Trimming does have its limitations. If you’re riding and the wind picks up or dies down enough that the kite size you have is unusable, then your trim strap isn’t going to completely fix the problem. In the case where the wind picks up, you’ll be able to de-power the kite but you’ll still need to change kites.
In the case where the wind dies down, if it dies down enough that your kite won’t fly, then no trim strap can fix that (at least not that I know of – if you find one, please tell me because I want it!).
Unlike sheeting, which changes the length of the back lines, the trim strap changes the lengths of the front lines. Doing this changes the angle of the kite in the wind (called AOA or Angle of Attack), which changes the kite’s power.
When you pull on the the trim strap, it shortens the front lines of the kite. It pulls the leading edge of the kite down, which decreases the power.
Trimming is not the be-all end-all for getting your kite to fly properly. It’s really only a way to tune your properly set up kite to the conditions and your preference.
If you’re having trouble getting the kite to trim correctly, or it does not fly properly, you might need to change where your back lines are connected.
Example – Say you launch your kite and have too much power. You use your trim strap to de-power the kite and still have too much power, so you sheet out. You sheet out enough to decrease the power, but barely so.
The problem here is not trimming; it’s that your kite is rigged for too much power. What you would want to do is land your kite and re-attach your rear lines further down to decrease its overall power. You’d then re-launch and try again.
Another Example – In the opposite case, say you get your kite in the air and don’t have enough power. You trim your kite for more power, but still don’t have enough. You then land your kite, re-attach the rear lines, and then re-launch. If in this case, you have enough power then you’re good to go.