battery not charging properly

743GUO · Post by **743GUO** » Sat Sep 01, 2012 3:34 pm

Wonder if anyone can hep. I have a 1961 G2 and the battery won't keep its charge.

I've done the charge rate test:
IGN on, Lights off gives 0.8amps (books says should be min 1.0); IGN on, Lights low gives 1.7 (cf min 1.3); IGN on Lights High gives 2.7 (cf min 1.0); EMG on, Lights off gives 0.7 (cf 6.0min).

Tried the "Low or no charge rate test" from the book - found it a bit confusing so may have done it wrong. Connected 1 Ohm resistor across multimeter terminals. connecting white/orange wires from alternator gave 1.5 to 2 AC volts with engine running, connecting white/light green gave zero volts. (may have them wrong way round - my wires are all different colours!) Did simple circuit continuity test on wires from stator & no sign of breakings in the windings.

Stator & wires look to be in good condition, rotor seems to be magnetised (it can hold a spanner).

Reached the limit of my limited knowledge & not sure whether I need a new stator or whether there's something else wrong.

Grateful for any advice.

Glen

saltbox alf · Post by **saltbox alf** » Sat Sep 01, 2012 5:54 pm

How old is your battery? If you have some charge being indicated then there is always the possibility that the battery is past it's service life

743GUO · Post by **743GUO** » Sat Sep 01, 2012 6:08 pm

Good question, but the battery is brand new - I've never even been down the road on it.

saltbox alf · Post by **saltbox alf** » Sat Sep 01, 2012 7:18 pm

Question? have you given it a charge after filling it and letting it stand for a while? Also it might be a good idea to trawl the forum archives as there is tons of info re charging , batterys, dynamos and altenators.
and proboboly answers to questions you have not even thought of yet.If you can't find an answer there or a clue, come back and I am sure the sages will have a crack at your problem.

Its not unheard of to have a duff new batteryEdited by - saltbox alf on 01 Sep 2012 6:19:44 PM

Colin F · Post by **Colin F** » Sat Sep 01, 2012 7:21 pm

You said you have done a circuit continuity test on the stator, did you continue and do the most important part of the test?

There must be NO connection between any of the leads and earth!

You should have a low ohms reading between each pair of wires, 2 should be lower than the other reading, if so that will identify the light green wire! (the wire that gives the low reading when paired with either of the other wires) that is because it is the centre tapping on the alternator.

743GUO · Post by **743GUO** » Sat Sep 01, 2012 8:53 pm

Thanks for the posts.

Batteru charge - I did charge it after filling it & its been stood for a good while. I'm pretty sure there's nothing wrong with the battery. I've had this low charge problem for a while & I've replaced/refilled/recharged the battery a couple of times.

Been searching the forum and the web for inspiration, but I can't find any! I'm not very good at bike mechanics & electrics.

Re the earth test, yes I did check that and there was no connection between any of the leads and earth. I haven't checked the resistance between each individual alternator wire, although I do know which the right wires are, even though mine are all different colours. What would that resistance test tell me?

Still not sure whether I should buy a new stator? If I do, do I have to buy the rotor as well?

Glen

saltbox alf · Post by **saltbox alf** » Sun Sep 02, 2012 12:06 am

Realisticly if you are unsure of what you are doing the best thing to do is join the club, find your local section and turn up.
It's better to find someone who can help you directly, I would not , myself, tinker with anything I was not really confident in tackling.

Cerberus · Post by **Cerberus** » Sun Sep 02, 2012 9:31 am

Best way of checking whether it is the battery or the bike is to remove the battery from the bike, charge it up with a battery charger. Measure the voltage immediately after charge. For a 6V battery should be at least 6.7V - 13.4V for a 12V battery (if my memory serves). Then leave the battery off the bike for a few days and measure the volts each day, if it drops significantly then the battery duff, remember 6V is a virtually flat battery and below that it's b****d.

Obviously if the battery holds charge off the bike, then something on the bike is draining it. Then it's a question of finding which bit.

GOLDSTAR · Post by **GOLDSTAR** » Sun Sep 02, 2012 9:43 am

all advice given you Glen is sound and probably the soundest is that od Saltbox Alf, if your not sure of what your doing Join this club, help advice and mostly good company. kind regards

743GUO · Post by **743GUO** » Sun Sep 02, 2012 12:48 pm

Thanks for all the commnts. In reply to goldstar, I've been a member for over 10 years but not a very active one. The nearest section to me is Bristol, and my "ode thumper" wouldn't get that far! We could do with a Wiltshire section, but I haven't got the time to start one.

PS the problem is definitely not with the battery.

Glen