I realize that adding resistors did increase the current draw for the signals - but a 50 watt resistor (6 ohms) doesn't draw more than the 2 standard bulbs in the stock signals. If the bike is charging OK with the stock signals (as mine is), there's no change in current, and the bike will continue to work as before.
Besides, turn signals are used intermittently. You can ride for hours, and use the signals once or twice - and the resistors are "wasting" no amps at all, because the lights are not lit.
I got the LED's for the signals because these lights turn on and off instantly, and to me at least - that seems more attention grabbing than a light that has to "warm up" - even if it's only for a fraction of a second..... (That may be due to some recreational substances I enjoyed back around 1968's effect on my eyes
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