nc24 charging

[dunc]

Hi all, my first thoughts when I purchased my friends nc24 being told it was killing the battery was that it must be the 'rectum frier'/ regultor, but after talking with the previous owner (another mate) who sold it to my friend before me, I've since found out that the rectifier unit is new and never solved said charging problem. Now this original owner is fairly well clued up and was of the opinion that the problem is very likely to be the 'dynamo' (?) chrging area in/around the engine (?) maybe this will need the coil to be re-wound or the 'pick-ups' are faulty? As you can probably tell I have no experience in this area and cant find any manuals so I dont know where to look on the bike, where to measure resistance, what amount of resistance to look for, etc... I know its always the same old problems with the charging on these bikes and to get the 'coil' rewound would be expensive but I really want to get this bike back to life, any help or ideas would be greatly appeciated, cheers guys Dunc

[beardsroad]

if it is the alternater coil that has gone i have a working one

[wullvfr]

because the bike has a reg/rec then it is a alternator and not a dynamo!!!!!

so you can do a simple check and test the output of the alternator to determine if it is faulty!!!

also check the charge rate at the battery and see how much of a charge it is getting,this will also determine what could possibly be faulty.

pm me if you want any tips on how to do certain checks with a multimeter


william

[dunc]

Sounds interesting beardsroad, will pm you with regards to your alternator! And thank you Wullvfr, I was convinced it would be an alternator, like my old suzuki was but everyone was telling me I was wrong! the cheek! Very happy to find out I was right, I will pm you when I have some more specific questions about doing the electrical testing, Thanks alot guys!

[Neosophist]

I've wrote loadsa guides on this forum for testing the altenator.

It's the same as the NC30 one, Electrexworld do a replacement for about £55.00 with 12 months guarantee if you wanna spring for a nice new one. It's G72 on their website if memory serves correct.

They also do a matching reg-rec too. (heavier duty wtih fins on it)

Anyways

Tests:

Unplug the plug from the reg/rec with 3 yellow wires going to it, these run from the 3 phase altenator.

Set the multimeter to AC volts and test between each wire and earth (frame), with the bike held @ 5000rpm you should have at least 50v on each wire.

You can also test the resistance by setting the mulitmeter to ohms and testing between each wire, it should be 0 - 2 ohms.

If it fails any of those tests it's knackered.

These tests are pretty good but since there is no load on the altenator even one that passes these tests may break down under load.

A knackered altenator usually kills the reg/rec and the battery too, hence you needing to replace all 3 parts.

To test the reg-rec measure the battery voltage, it should be 14.1+ @ 5000rpm too.

Any higher or lower and the reg-rec is suspected.

If the altenators gone its' probably killed the battery and the regrec too if it's been run any miles, I drove a 24 150 miles home not too long ago and had to put a brand new battery I brought up there on to make it run, by the time I got home battery was shafted due to bad altenator and reg/rec, wouldn't hold a charge.

Hope that helps

[wullvfr]

Set the multimeter to AC volts and test between each wire and earth (frame), with the bike held @ 5000rpm you should have at least 50v on each wire.

for this test you don't have to earth the negative probe,you test between two of the yellow wires and so on until you take three seperate readings.



william

[Neosophist]

your confusing the ohms test and the voltage test.

you test each yellow wire and earth for voltage, each wire should have 50v, theres only 3 wires to check, not a combination, thats the for ohms test.

you dont' test the voltage between each yellow wire.

[wullvfr]

im not confusing it with the resistance check at all

neo,do you still have the fault finding diagram for charging problems

look at it(section b) and you will see what to do for testing the output of the alternator.......

this is exactly what is says

connect the multimeter leads between two of the three yellow wires coming from the stator.start the engine and rev it to 5000rpm,take the reading.switch one of the multimeter leads to another yellow wire,and so on.

now,according to the diagram you can do a resistance check by earthing the negative probe,this is the check above the alternator output check,is this the one you are confusing it with?

you can also do the resistance check you are talking about,where you put the probes between the wires.



william

[wullvfr]

i checked the voltage output of my alternator today just to be sure,and the correct way to test it is by checking between two of the three yellow wires.

if you do it by earthing one of the probes it just gives you false readings.



william

[dunc]

Thanks guys, I will be getting a battery and testing electrics very soon, rebuilding carbs now and hopefully can have her running but tatty for the 'summer' ( or whatever bits of sunshine we're lucky enough to get) then she can have full rebuild next winter.