Battery keeps going flat ?

[fuzzy139 0]

Hi all, got my son a CPI GT 50 to start his bike career off, but we are having some problems with it... The fully charged battery will go flat and the bike will not start , this is only after 3-4 hours without even the ignition on, any ideas ?

many thanks

[gravelrash 0]

Hi Fuzzy, welcome to the forum! (whoops! actually joined 2011,hi anyway!! )


The first thing that came to mind when I saw the title was an alarm problem cos they are a pain!
but if its going flat after such a short time the battery sounds as though its had it.
Static voltage test
If you can put a multi-meter on it set to DC 20v range and check the voltage, you need it to be checked at least an hour after any charge you may have done 12.7 volts should be about right.
Starting load test
Put your volt-meter back on the battery and try to start the bike if the reading drops below 9.5 volts the battery has a low capacity and should be replaced.
Charging system test
start the bike rev to aprox 3000rpm and check the battery voltage should be approx 14-14.5 volts
This is all general to any 12v system and your user manual may have more specific information about charge levels
hope you get it sorted Fuzzy keep us informed and hope this helps a little!

[stantheman 0]

i would say it needs a new battery as well

[gravelrash 0]

If the bike doesn't have a rev.counter (for the bike charging test)these are a good buy, easy and accurate to use for tuning and fettling got one for my daughters XR125 can get 4 stroke or 2 stroke versions.
http://www.ebay.co.uk/itm/New-Motorcycle-Motorbike-engine-RPM-counter-Tachometer-Hour-Meter-2-stroke-UK-/230977796485?pt=UK_Motorcycle_Parts&hash=item35c7597985

[haveugot1 0]

Nice one mike some good info there.

[Grumpyowl 0]

I know Nothing,
But I bet it's Knackered and you'll need a new one

[Chadatious 0]

Sounds knackard.

My ones keeps dieing over 24hours but trying to avoid replacing it at min due to buying fish tank bits

[trebor4460 0]

new battery by the sounds of it.

[Neill 0]

agree with the above. sounds as if badly sulphated internally causing it to discharge

[fuzzy139 0]

Hi all, thanks for the replies,the battery is a new one ! the voltage is 12.89 on a multimeter,getting frustrated now , I hate electrics. I will try unplugging things and see how it goes ! to see if I can trace it.

ta
shaun

[dick65 0]

you sure its charging?
try taking it for a good run ,just starting a bike takes a bit out of it

[gravelrash 0]

Your static voltage test looks good Fuzzy but try the load test, are you sure the battery has gone flat and its not the starter relay or a starter motor fault?

[dick65 0]

@gravelrash wrote:

Your static voltage test looks good Fuzzy but try the load test, are you sure the battery has gone flat and its not the starter relay or a starter motor fault?

[lee1 1]

I would still follow the advice

if its going flat inbetween 3 to 4 hours
without the ignition on I would say a possible battery fault as I couldn't see anything on a bike to pull enough amps to make the battery go flat in such a short time

even though the battery is new don't forget
it could have been sat on shop shelf doing absolutely nothing for god knows how long
not uncommon to be sold faulty battery

only other test I can think of is to do a battery drain test,using milliamps on the multimeter

then pulling the fuses one by one to see if anything else is draining the battery

look up battery drain test on youtube

[Davehutch-hutchs 0]

some good advice from the lads there fuzzy139 hope you get it sorted

[fuzzy139 0]

Cheers guys, will be on to it again tomorrow

[Davehutch-hutchs 0]

@fuzzy139 wrote:

Cheers guys, will be on to it again tomorrow

let us know how you get on m8

[fuzzy139 0]

Didnt get much time today !!! too sunny but I checked the loss at the battery, 0.5 , which does seem ok, I think I will get it insured and give it a good run and see what happens, just need to fix the number plate holder.... theres always something #gaffatape !