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Battery not charging - what else to check

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MarkCR750:
With the bike running put the multimeter across the battery terminals (set to the 20v range), rev the bike up to 3k revs and you should get approx 14.2v, if you don’t it’s your alternator or associated wiring, if you do get 14.2 then it’s the battery that’s not holding it’s charge, if you get more than 14.2(ish) then it’s the reg rec,

Underdog1:

--- Quote from: MarkCR750 on October 04, 2018, 08:59:29 PM ---With the bike running put the multimeter across the battery terminals (set to the 20v range), rev the bike up to 3k revs and you should get approx 14.2v, if you don’t it’s your alternator or associated wiring, if you do get 14.2 then it’s the battery that’s not holding it’s charge, if you get more than 14.2(ish) then it’s the reg rec,

--- End quote ---

Yeah not getting any increase so must be the alternator playing silly buggers

Bryanj:
Not necessarily mate, reg/rec may not be working new or not or the wiring/connections may be dodgy, either is far more likely than a duff alternator. Only bad alternators/field coils i have ever seen duff in 35+ years were mechanically damaged

SteveW:
http://blacksquaremotorcycle.com/electrical-system/

http://motorcyclemd.com/how-to-fully-troubleshoot-your-motorcycles-charging-system/

To check the stator measure any 2 yellow wires resistance, should be fairly low ohms (bike not running)
Any yellow wire to ground should measure open circuit.

Bike running, any 2 yellow wires, AC volts around 20v upwards depending on engine speed.
If the meter reads a few milli volts AC on any 2 yellow wires the stator is working, the exciter coil is not, check the voltage (DC this time) to the exciter coil, between white and green wires or white to ground. (this was on my 550 so colours may be different)

I was convinced for ages my stator was faulty on mine, turned out to be a break in the wiring to the exciter coil.

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