Reply To: Power problems – GT650
The first thing is the charging, it sounds like the regulator/rectifier has gone. If the voltage is to low the ecu will not load properly & basically trys to set a base line to allow the bike to run, first check the stator with a multimeter you will find a plug with 3 yellow wires set the multimeter to resistance hold it on one terminal & touch the others in sequence so 1-2-3, 2-1-3 they should all read something like 0.1, 0, 0.1 if any of the readings are above 0.2 or infinity then a phase has burnt out, you don’t at this stage need to measure the ac output as in my experience if the resistance is right then 99.999% of the time the output will be fine, next set the multimeter to dc start the bike & measure across the battery the voltage should even at tickover be above 13.6v increase the revs it should ideally read 14.3-14.4 v if all good if it doesn’t then the reg has gone, carry this out first & report back.