Battery voltage

I have had a nagging intermittent problem with starting my bike.
The bike is a XJ900RL.
I bought it Oct 2015 and the guy told me that the battery was quite new.

I found that if I start the bike and it stalls before warming up, it can happen that she simply will not kick over again.
I found that if I connect up the battery charger and then either top up the charge on the battery or try starting her up with the charger connected, she goes.

hmmmmmm

The stark plugs are new.
The rest of the electricals are stock and probably never replaced since new.

Now the battery. After a fresh charge, I measure 12.78v at the terminals with the bike off.

Me thinks that this is a little low. And if the battery is in fact a tired unit rather than nice and fresh as I was lead to believe, then one failed start may bring that voltage down to a level where there is no longer enough juice to feed the spark plugs properly any more.
Also this could be the straw that breaks the camels back so to speak if there are some other tired components in the electricals.

What do you guys think? Is this enough juice for a (relatively) fresh battery?

Also I see that the water level in the cells is either within the tolerance or 2 of then are a tad high. Is there are down side to too much water apart from overflows?

 

it is battery acid in the cells and water evaporates from each cell you can even them out by adding distilled water to the cells

look in the information over load
under
How do I know if my battery is good?:

http://www.xjbikes.com/forums/threads/the-information-overload-hour.27544/

from that source
the battery should read a minimum of 12.8 volts DC.

the test specs
For all XJ-series models, the maximum available charging output VOLTAGE should be as follows (all values are approximate):

* approximately 500-2000 rpms: 1.8 volts gradually increasing to 14.2 volts
* 2000+ rpms: 14.2 volts up to about 14.8 volts, with a maximum of 14.8 volts (all models except XJ700-X and XJ750-X)

you should eveluate your charging system .
could be your brushes are bad or the copper rings are dirty in the alternator , battery treminals dirty the negitive wire connections at frame and moter could need to be cleaned. voltage regulator connections need to be cleaned ect....

every thing you need to know and do is in the info overload link


measure the voltage of the battery when you start it and shut it off . starter not spinning after a start and shut down could be a problem someplace else like starter, solenoid
clean those connections too.

 

Leave your meter on the battery after you unhook it from the charger. Watch to see if the voltage stabilizes, or if it keeps dropping.

 

Standing voltage seems about right, could be higher, what matters is what happens to the voltage under load, when starting. Put your meter on the battery and see if the voltage drops when starting.