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Honda CB125 K3 charging problem & starting motor

2K views 3 replies 2 participants last post by  ajk4send 
#1 ·
Hi,

I have a honda cb125 k3 which is 6V.
When the bike is running and i measure at the battery its 8.3V.
If the battery is disconnected and the bike is running its around 15V.
Is this normal? how much voltage do you need? rectifier still ok?

2nd, when the bike is not running but on and i measure at the battery i get 6.3V.
If i try to start with the starting motor it goes for 1 try but fails after that and then the battery is 2.3V
Even if i drive for 1 hour and stop the motor and try to start it with the starting motor its the same thing...
The starting motor did work...

i've read also on the forum maybe to change the rectifier and buy a voltage limiter/rectifier for a new one.
Do i need to do this? And what do i need to look out for/ask.

Thank you
 
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#2 ·
Voltage with locked starter should be around 2,3 V with 300 A current. With loaded starter it should be 4.2 V. Look at manual page 190
 
#4 ·
Locked starter means, that starter is "on" and is not turning. In our bikes charging voltage depends on load (lights on/off) and engine speed.

Please, take a look at the table on FSM page 190. There are battery voltage and charging current values at 3000, 5000 and 10000 rpm.
 
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