NC30 battery question

[magg]

Are you sure you got 14.3 with light and 12.9 no lights? I would expect 12.9 with lights and 14.3 with no lights if one of the yellow wires is broken. Just repair the broken yellow wire and check the others from the stator to the reg/rect and then recheck the battery voltages. If you get 14.3 with lights on at 5000rpm then all should be ok.

[Neosophist]

I've got an update...

I bought a new varta battery off Rick on here. I've fitted it and done a couple of journeys since. Last night I tested the voltage. The results were as follows:

Battery on it's own 12.98
Idle 12.9
5000rpm with lights 14.3
5000rpm no lights 12.9

I then took the fairing off to check the regulator and the right hand yellow wire has completely burnt and snapped. Am I right in saying that this is more than likely an alternator problem? Is it worth doing any other checks? I know there is a lot of info on this but I want to make sure I get it right.

Thanks
Andrew

Repair the broken wires with solder, crimps are no good.

Looking at your voltages, re-test after repairing and if it's still 14.3 with lights on at 5000rpm you should be all good

[aka0019]

Right i've soldered the damaged wire and re tested. I think the wiring has been modified before though as you don't plug the whole lot in like some I have seen. They are all seperate with spade connectors on. Anyway the results were:

5000rpm without lights 13.9
5000rpm with lights 13.3

I know that I need to do further tests with the yellow wires now so will do that another day. I just thought I would update though. One question regarding testing the yellow wires as I can't seem to find my answer by searching...do I test the voltage between them while they are plugged into the reg/rec?

[hardnutdvd]

im unsure what u mean.
they are all seperate?
do you mean seperate going into the reg/rec or all seperate on the right hand side of the fairing just under the infill panel where it would normally be a block connector with all three going in one end and and coming out the other side?

unplug it near the infill and test each wire seperatley with the engine running. iirc you put the red probe onto one yellow wie and the black (-) probe on the frame.. do this with all three yellow wires in turn. you should be getting 45-50v on each one.
the yellow wires go to the reg/rec from the block connector, i dont think it matters they are all seperate and can go on any of the three connections in the reg/rec that are for the yellow wires, you dont wanna mix up the other 2 (different coloured wires) going into it though.

[aka0019]

I mean the wires that go into the reg/rec are all seperate and not in a block.

I thought that you tested the yellow wires between each other and not between the frame? Sorry if i'm getting confused.

[magg]

Yes test each yellow wire to the other yellow wire. The wires at the rect/reg, three yellow, one red and one green, should be in a block that keeps them from being mixed up.

[hardnutdvd]

ah right. ok.
the wires should be going into a block at the reg/rec. not having a block indicates that the plug that is on the original loom would have corroded or burnt out, leading to someone creating individual connectors plugging into the reg/rec.
this aint a problem as long as they are not touching and kept completely isolated from each other. and of course that the red and green are correctly placed

i cant recall 100% wether you test between each yellow wire or by grounding from the frame. try both ways and see what readings you get. when i get home i can check my manual and let you know for sure.

[CMSMJ1]

you check AC output using the yellow wires
you check resistance using the yellow wires

wires a,b,c
a+b
a+c
b+c

sorted..

[aka0019]

Right then, before checking the yellow wires I noticed the other two looked a bit worn so I have cut them down and soldered new wires and put new spade connectors on. The wire I used was 17 amp stuff from Halfords, I was told that would be fine for the job? The results when testing between the yellow wires after doing that were:

39
41
44

Am I correct in saying that this indicates the alternator is the problem? After testing the wires I connected them back up and checked the battery on it's own with the bike off and it was about 12v. Then when I tried to started the bike just died and wouldn't start. Could that happen even though the battery was showing 12v? Since having problems I have used the bike on a few occasions so not sure if because of the alternator it has killed the battery? I thought this was strange though since like i've said it showed 12v?

[magg]

Fix the broken wires first and then retest battery voltage. Your charging voltage readings where pretty given that not all the output of the alternator was getting to the rect/reg.