Hi, Andy.
Thank for the advice.
I ever check with the workshop before and their reply to me is the charging is good.
Never change the reg or check before, as their reply is that i am having a good charge by measuring the battery at the + and - pole with the multi-meter.
Have already change a few new batteries, all of them will be running well with two 12 volt 65/55 watt bulb for about 3 month, after three month the voltage runs low and i have to disconnect one bulb in order to start.
Manually take out the battery and charge will run another three months, and after the same thing happen.
Have check with most of the MC28 rider here, all of them are having the same problem. And most of them are running with one 12 volt 35/35 watt H4 light bulb. That is why i am consider using two 6 volt bulb, as i prefer to run the bike with two bulb then one.

Thank you.