Battery voltage too high.
Motorcycle battery voltage too high.
In order to get maximum battery life proper charging voltage must be maintained.
One item of note.
The only other battery i ve used for my bike was a regular lead acid battery.
Yes a bad regulator will cause your motorcycle battery to be overcharged.
My new battery s voltage from the factory unused read 12 9 v but after using for about half a week of use its holding a.
It should be between 12v and maybe 14 8v max.
That voltage seems a mite high.
The old one usually read 12 5 v give or take on a dmm.
Can t do better than that.
You don t say whether this is on the bike or on mains charge.
If the battery begins to hold and then steadily drops in voltage there is a problem.
Measure the battery voltage while the engine is running.
With a voltage between 12 and 15 8 volts dc.
If you see something like that right after you charge your battery when re testing you might want to turn the headlights on for 30 seconds or so and re test because batteries can keep a superficial surface charge revzilla photo.
We call this the open cell.
The battery is a little pickier below 13 8 the battery will not fully charge.
This is a common failure because of the way motorcycle alternators work.
The 16v you describe is definitely too high for charging a 12v battery 14 4 volts is a suggested maximum.
If the voltage instantly drops to 0 volts that is also a problem.
Either way high or low charging voltage can lead to battery problems.