Battery not charging

Hi,

Son's CG125, new battery (we think), but it's not holding charge (on mains
charger), so something broken it...

Likely cause?

TIA

 

Is there any acid in it?

 

Reg/rec. If it's an old 6v one, they are very cheap. Even the later 12v
ones aren't too bad. But check the connections to the unit first - if
he's been riding it in this weather it could just be a corroded
connector block.

Shove a multimeter on it first. A 6v system should show about 6.8v on
full charge. A 12v one should show 13.5v. If you're getting that across
the battery terminals, then it's charging Ok and it's a stuffed battery.

 

new battery (we think)

Sealed dry unit.

 

Son's CG125, new battery (we think), but it's not holding charge

Will check this and voltage - it's a 12v battery.

Thanks.

 

Could be dry now if its been overcharging.

They have vent valves so excessive gas pressure can escape, but you have to
pry out the glued in covers and the rubber vent caps to replenish dried out
cells.

Might not work on glass-mat gel types.

 

what type of charger? Some sealed types of battery, especially AGM, won't
recover with older types of charger, including Optimate 1,2 or 3, if they
have been totally discharged.

 

A cheaper end one from Argos...

 

which says "suitable fior use with wet Pb/acid" batteries

get a CTEK XS800 for about £27 (assuming it is a 12V bike)

 

Jumplead the suspect battery to a good one to get enough voltage to
let the charger take over.