2008 GV125C headlight/running issue

Hi,

Have you check your battery voltage ? At low regime, it must show 14 V. If not, either alternator or regulator might be damaged.

If you are sure that the new regulator works well, you should check the alternator. The battery is only use for starting and after, the regulator provide the power required for the operation of the engine and accessories.

Hey,

As Daniel says too, I have my suspicions on the regulator.  How about this, what i’m about to say is direct of the workshop book I have been reading…

1. Start the bike, Rev to 2.5 – 3,000 rpm.  It “MUST” say  14.5 or over
   Any 13v readings whatsoever = The regulator needs inspecting/replacing.
   OEM rating = 14 – 15 (15v best)
2. What lights do you have ? – main headlight bulb must be 55w max  (Some OLDER GV bikes need 35w instead)
3. Depending on your model – If there is a “HYOSUNG” 30/20A relay on it, inspect that one too.   I know it’s on ALL GTR bikes to power their dual lights.
4. Battery will be 12.8volts when bike is OFF (charged)
5. Switch on the bike -> Don’t start -> Put All lights on.  The battery must not DROP by 1 volt.   (12.8 dropping to 12.6 is normal)

Let us know how you get on!