I don't know exactly what you mean by hyperflash but the ones I've seen flashed at about 500ms on 500ms off vs 1 sec on 1 sec off. Was not fast enough to look like a strobe.
Why do they flash faster without loads? I thought thermal flashers were a thing of the past and replaced by electronic flasher units.
Actually, I remember with the thermal flashers adding more load would make them flash faster.[/QUOTE
Ok let's go over these questions one by one lol, whenever a bulb on your vehicle (or most of them) burns out for example a front turn signal, the vehicle will "let you know" the bulb is out by making the bulb flash really quickly, kind of like a bulb out indicator, now here's why a led bulb makes the cars blinker blink fast, led bulbs don't pull enough power since they don't need too, they can produce 2 even 3x as much light as a incandescent using a fourth less of power, now here is where it gets weird, the vehicle can tell if there is a load, (from the old 30-40 watt bulb), if it is not pulling a specific wattage it will trip the cars "bulb out" function, so therefore you need a resistor to "make the car think it's actually pulling the true 30/40 watts of power, do a quick youtube search of led hyper flash.