Clutch The KTM 250 EXC-F employs the KTM-developed DDS clutch (damped diaphragm steel) with a wear-free steel basket and extremely heat resistant clutch plates and new, nitrated steel liners. This clever design employs a diaphragm spring instead of the usual coil springs, making for considerably easier clutch action.
The difference between active and passive solar water heating systems is that active systems have circulating pumps and controls, while passive systems do not. Although passive systems are usually not as expensive as active systems and can last longer, they are generally less eficient.
A solar pool heater can be less expensive up front than an electric heater, heat pump, or gas heater, depending how large your pool is. Once a solar pool heater is installed, you heat your pool for free. With an electric or gas heater you need to pay the electric or gas company depending on how much you use the heater.