Herk-thanks for posting comparative readings and temps! Really drives home the point.
The old design shunt type regulator sheds heat by design ....as it ages working harder..nearing 15v, the resulting intense heat can internally damage the regulator, harden associated wiring, burn connectors and damage the battery via overheating (commonly evidenced by boiling away the electrolyte) ...even blowing bulbs.... its overcharging the whole system.
Obvious that the lower Mosfet voltages are more than sufficient to supply power (system wide) and recharge your battery...meanwhile producing much less heat...a longer life all around with the Mosfet = long term RELIABILITY.
Mosfet conversion is now a common, widely known upgrade to many bikes, not only the EX.
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