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.
One advantage of active heatsinks is that they tend to be more compact than passive heatsinks. Since passive heatsinks do not have a fan or other means of moving warm air away from the heatsink, they are physically larger to conduct heat away from the hardware. Some technicians prefer passive heatsinks because they have a more even and predictable method of heat transfer than an active heatsink.