Battery reading

[stowei]

Have been getting closer and closer to failure with starting after a cold weekend so picked up an Optimate. Charges to 14.3V after a few hours on the Optimate but if the battery is then left overnight (charger off) the reading is down to 12.5V the following morning. That is sufficient to start the bike but does a drop-off rate like that indicate that the battery is near the end?

GS1150 2002 although I guess that doesn't make any difference.

Thanks

Ian

 

[John Armstrong]

Best battery test is if it starts the engine ok.

My 07 GSA is about 12.9v, 24 hours after being up at 14.2v on charge, if this is any use. The difference might be how accurate my DVM is

 

[cookie]

how i test batteries:

1) do a load test on it. testers are about £25 in machine mart.

2) stick a hydrometer in each cell to see if they are all holding the same charge. this doesn't work that well on gel/AGM batteries

 

[Stewart H]

Voltage readings are hit and miss at best, surface voltage will tell lies,especially with a recently charged battery, a Hydrometer can be effective if theres enough electrolyte.
Stewart

 

[D6]

charge reading is always higher than batt voltage reading,12.5 to 13v is ok but still doesnt always mean itl keep that charge,or recover back to it after starting,if the battery feels tired replace it,you will wish u had when it fails you when you need it