Charging voltages are only approximate. Any voltage between 13,5 and 14,5 are OK. The battery itself will charge as soon as the voltage is above 12.4 V.
Why did you start measuring in the first place ? Did you have any problems ?
If it ain't broke, don't fix it.
_________________
Poul
"If Life Gets Boring, Risk It!"
MC21SE, KISS box
MC21SP, HRC box, racing loom