New battery dead?

[tojo82]

Hi all I've been having problems with my bike sv650s k3 with no power to the front dash. It has a new battery a motobatt so I assumed it would not be that. I chased around the green connector and all the wires looking for any damage and so on. My friend came over with a voltmeter yesterday and the battery only has 4v? It is less than a month old and I've not ridden the bike yet as I've been bringing it back from the dead after sitting for 2 years. We jumped the bike and when revving the engine the volts jump up at about 13 but when the engine turned off the battery quickly drops to 4v again and won't give enough power to start the bike? I have a few options I guess charge the battery and see if it fixes itself? Replace the battery? I googled and read it could be a r/r not working properly? Any advice would be great please

[Seeker]

If the battery has dropped to 4V it may now be damaged. Assuming it isn't then running the bike a few minutes won't be enough to charge it, it would need to go onto a charger. Some battery tenders won't handle a battery whose voltage has dropped too low.

You'll need to check that you don't have something on the bike that is draining the battery (once it's charged) - you'll need a meter set to DC amps (set to 10A initially), you usually have to put the meter's positive lead into a different socket on the meter itself when measuring current. Connect the meter between the battery plus terminal and the leads that would normally go to the battery plus terminal (do not try and start the bike like this it will melt the meter, don't turn on the ignition either). The battery neg should be connected as normal. There should be a slight reading but it would be in the milli-amp range - so with the meter set to 10A, drop the range until you get a reading, it would typically be 20mA (estimate).
If you have a much larger number you would need to start by removing fuses and unplugging things and see when the current drain drops.


When everything has been returned to normal and the bike is running you should be measuring about 14.4 V DC across the battery once over idle.

[tojo82]

Thank you for your comprehensive message

[NTECUK]

A dc clamp meter is not that expensive.
They are available on amazon and will help you check your charging system once you have fixed the standing drain.
"Digital Clamp Meter TRMS Auto Ranging 5999 Counts".
Is cheap and easy to use

[Dave20046]

Originally Posted by NTECUK

A dc clamp meter is not that expensive.
They are available on amazon and will help you check your charging system once you have fixed the standing drain.
"Digital Clamp Meter TRMS Auto Ranging 5999 Counts".
Is cheap and easy to use

They are (or were at the weeked) £2.99 in lidl.

[Adam Ef]

Worth checking the battery. I've heard of a few Motobatt batteries that have been dead on arrival.

[Biker Biggles]

If you bought new first get the battery replaced under warranty. Despite all the official advice I like to trickle charge a new battery before use as I have found they last longer that way. Then do all the above checks to ensure the bike leccy is all in order and there is no battery discharge when it is switched off and it is charging properly when running.

[tojo82]

Just a quick note to say old one returned and replaced with a yuasa bike has passed its mot and its done more miles this week than it had in the last 2 years!

[SV650rules]

You need over 14.2 volts to keep a 12 volt battery in good shape - 13.7 volts is the 'float voltage' which will keep battery on a low trickle charge ( sort of voltage that the battery maintainers settle down to when they are happy with battery ).

As soon as the OEM battery on my 2016 AL7 packs up I will be getting a Yuasa AGM, I have done this on other bikes and had no regrets, got Yuasa Silver batteries on our cars as well. I used to work at a company making battery production equipment and Yuasa was one of our customers, their R&D, technology and quality control was way ahead of others.