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battery going flat?

Posted: Thu Jul 10, 2008 7:18 pm
by Drunkn Munky
The battery on my NC35 is going flat over night, is there any common problems i should be looking for? the battery is new and charges well.

Re: battery going flat?

Posted: Thu Jul 10, 2008 7:54 pm
by aaron0288
sounds to me like your reg/rec has fried itself.

Re: battery going flat?

Posted: Thu Jul 10, 2008 9:58 pm
by wullvfr
if the battery is in good condition and holds a charge then its strange that it goes flat over night....unless the reg rec is fried......get the multimeter out and check to see if the battery is getting a charge whilst the bike is running....and then see from there,it should charge between 13.5-15.5 volts @5000rpm. :D :D

Re: battery going flat?

Posted: Thu Jul 10, 2008 10:12 pm
by Neosophist
Leak test would be the first thing to check..

You'll need a multimeter and some common sized tools.

Set the multimeter to amps.

Disconnect the negative lead off the battery and put the postivie probe of the multimeter on the battery lead and the negative lead to where the earth strap bolts to.

With the ignition turned OFF you should have less that 1ma on your multimeter, anymore than this and something is shorting to earth causing your battery to drain.

If the current leak is high start unplugging things until your current leak disappears.

Whatever you unplug to stop the leak is either buggard or there is a freyed wire somewhere causing the short.

Hope thats of some help

Re: battery going flat?

Posted: Fri Jul 11, 2008 9:31 pm
by NC30-BADBOY
When i bought my bike i unfortunatly go mugged by the twat selling it because he fully charged the batt before i came round.
My first thought was the reg/rec but when i went to change it i noticed the connecting plug had corrosion on the contact points so i cleaned them up before changing the reg/rec and it worked fine enabling me to take the reg/rec back and save myself some money.

Re: battery going flat?

Posted: Fri Jul 11, 2008 9:35 pm
by Drunkn Munky
ok i have a multimeter but no clue how to use it and i cant find the instructions, from the pic can anyone tell me which holes the probes need to be in and what setting the dial needs to be on.
Thanks
Image

Re: battery going flat?

Posted: Fri Jul 11, 2008 10:33 pm
by wullvfr
for checking the charge rate,plug the black lead into COM....and the red lead into V to the right of it.turn the dial to the v setting the one that starts 200m and put it to the 20.....then test the charge rate of the battery with the bike idling 5000rpm.for the leakage test you need to put the red lead into the A and turn it to the amps which is the one its on in the pic...always start with the highest one in this one then work your way down.

Re: battery going flat?

Posted: Sat Jul 12, 2008 2:39 am
by Neosophist
Did you get it tested?

If not heres some step by step instructions for your meter...

The charging test is easy, lets start with that.

Like WullFVR rightly said. Put the black lead in the COM, and the red lead in the V, to the right of the black lead. The picture you posted shows the multimeter set to 2amps DC, we'll get to amps / leak test next. Going back to the picture, the opposite end of the knob is in the DC Voltage section, which is what we'll need to check it's charging the battery, so flip the dial the opposite way around and then down one more to '20'

Make sure the battery is fully charged before doing this test, after charging it up, connect the multimeter (as set above) to the battery (with the engine off first of all) the end of the red lead to the Positive (+) terminal and the end of the black lead to the negative (-) terminal, a fully charged battery should show aroudn 12.8 on the meter, any lower and check the batterys charged.

Now, start the bike, warm the engine a bit and hold the RPM at 5000. (It's easier if you have someone to help) Put the meter back onto the battery like before, end of the black lead onto the Negative (-) terminal of the battery and the end of the Red lead onto the Positive terminal of the battery (+).

The multimeter should now show between 14.1 and 15.1v if the charging circuit is working properly, anything outside this range points to a knackered reg/rec, altenator wiring or at worst case both.

Leak Test.

Ignition off!

The picture shows the meter set to test for upto 2amps DC, thats fine so leave it at that, the black lead stays where it is in the meter, but put the red one in the hole to the left this time, (marked A). Disconnect the earth cable from the Negative (-) terminal of the battery.

Put the end of the red lead to the cable you've disconnected and the end of the black lead to the battery terminal.

Your meter should show 0.01 or less, if so you can bring the meter down a setting (200m) instead of 2, keep bringing it down a notch (move the dial clockwise) until you get a reading, you want a maximum leak of 1ma.

If you don't have current leaking to flatten the battery, it stands a chance that the battery is fooked, when this happens they short out inside causing discharge over-time... the most common cause of this besides the battery being old is being over-charged, so if it comes to replacing the battery, double check your charging circuit again!

Hope that helps!

http://www.akhara.com/nc30/nc30manuals/ ... 0R_C15.pdf

Pages 5, 6, 7 in that NC30 manual detail how to test the reg / rec also etc

Good luck!

Re: battery going flat?

Posted: Sat Jul 12, 2008 4:42 pm
by Drunkn Munky
hi yes that helped, done the tests, there was no leakaged reading all from the leakage test and the chatging test showed just over 12 volts with the ignition off and 13.7 at 5000 rpm, a bit below but all light were on as they cant be turned off on the rvf

Re: battery going flat?

Posted: Sat Jul 12, 2008 6:23 pm
by Neosophist
That is a bit low... even with the lights on you should still have 14.1 / 15.1 volts as the laternator produces about 65 volts at 5000rpm and the reg / rec reduces it.

Could just be a knackered battery dischargin itself.

Next step i'd do is charge it up till it's full, measure the voltage with the meter and leave the battery off the bike for a day or two and measure the voltage again. If it's going flat by itself after a couple of days its knackered.