Hello,

I have some problems with my original battery (GS Yuasa GT9B-4). Could you please check what's your fully charged battery open circuit voltage. It should be measured min about 1h after charging)?



Mine is showing 12,43V after charging, lights, immobilizer works ok but I still can't start the engine. I can hear the pump but the starter is just clicking (click-click-click) but nothing happens.

Thanks!!

what voltage do you get when the headlight or a big consumer is on as it will be the ampage of the battery that has crashed not the voltage(with cars we say anything below 10.5 under load is dead) (on a fully charged battery that is)

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Yamaha xt660x 2009 blue/gold mods= iridium plug, stage1+2, removed snorkel, blocked ais, akrapovric pipes, power commander pc3usb (pre made map), adjusted tps, dynojet 02 optimiser 30amp aux relay, smoked puig screen, oxford heated grips and brembo carbon ceramic pads, rfx 30mm bar raisers, puig long adjustable leavers, plus much more and a cheep �30 alarm which stopped it been stolen

I checked the battery after charging during this weekend:

open circuit 12.49V
connected and lights on 11.69V
trying to start the engine 10.something V
after trying the starter 11,29V

...so it looks like it's over.

Which one do you reccomend to buy? I can't see any GS Yuasa GT-9B-4 available now at the moment here in Poland. They show only YT9B-BS.

i think that your battery is ok.you need to buy new brushes for your starter.try to hit the starter with a wrench when you push the start button.if the starter turns with this , just change the brushes.

How old is your battery?

12.6V is a fully charged battery and it should only drop about 2V from your open circit reading when cranking.
You are starting at 12.4 and dropping to 10v when cranking...battery is dead.
You can confirm this with a load test but I will bet my good battery on it!!
Your lights on test is a good indicator of load, it should maintain above 12V with lights on and the fact its not...battery has no capacity.
Once you get this sorted you will need to throw the DMM (meter) onit while the engine is running to ensure that the charging circuit is ok. It could be the reason your battery is dead. While running the output voltage syhould be between 13.5-14.5V and not go over 14.5V when revving it.

Matt.

I connect one of these up when ever the bike is in the shed. The open circuit voltage is always 12.9-12.7 volts and it stays like this for days with the charger only monitoring the voltage and not actually charging.

Have a read through this Yuasa PDF Section 3 is all about Inspecting, testing and charging.

Methods of Checking Battery Condition
Hydrometer Voltmeter

100% Charged 1.265sg 12.60v
75% Charged 1.210sg 12.40v
50% Charged 1.160sg 12.10v
25% Charged 1.120sg 11.90v
0% Charged less than 1.100sg less than 11.80v

Thanks for answers!! The battery is