Bladders are thin rubber tubes that are inflated into the struts and leading edge of a kite, giving the kite its aerodynamically stable shape. The bladders are pre-formed and the solid material of the kite gives a stable overall shape when the bladders are inflated with the correct pressure.
Bladders are the most frequently needed spare parts for a kite and therefore it is useful to find out before buying how the kite manufacturer ensures the supply of spare parts and how expensive spare bladders are in case of doubt. Our own brand Ozone stands out from the crowd of kite manufacturers in this respect, and also supplies complete bladder sets with Leading Edge and Struts bladders for old series for a very long time at a price for which other manufacturers sell individual bladders at best.
We recommend, especially when travelling, to have such a replacement Bladderset with you to be able to enjoy the day on the water again immediately in case of an emergency.
The front tube of the kite is most often affected by damage. The Leading Edge Bladder can burst in case of hard crashes on the water or when the pressure is increased due to strongly rising temperatures. There are also specialists who inflate the kite too much from the outset and cause the final bang while still on the beach. Often, however, material fatigue also plays a role here.
To avoid damage caused by pressure, you can use a pressure gauge when inflating the kite and should check and adjust the pressure in the tubes in case of changing temperatures or sudden strong sunlight.
Too little pressure or a drop in pressure will cause the kite to lose its aerodynamics. The kite will then fly significantly worse, cannot be steered well and cannot be launched.
Changing bladders in the kite is a rather thankless task, although you can easily get the bladders out through the openings provided at the tips. But don't forget to knot a thin line to the bladders and pull it through the tubes with which you can pull the bladders back in later. When pulling in reappeared or new bladders you have to be very careful that the bladders do not twist in the tube. An overlooked twist can ruin the work and lead to another bladder change. Especially the pulling in of the front tube can be complicated, as there is a lot of frictional resistance to overcome towards the end. Here it helps to rub the bladders with soapy water beforehand or to sprinkle the bladders with talc powder to reduce friction.
Inflating the bladders after changing them must be done slowly and carefully so that any twisting in the hose is noticed in time.