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My NC 250 has never let me down with a flat battery but as I always give it a booster charge before use its hard to say whats going on. It has the 60 watt 2 wire alt with the grounding coil wires linked in series and a modern combined rec/vc unit under the seat. The headlamp internals look pretty std .I'm thinking of fitting a charging light in the HL but have little idea of the best way to do it, The bits on E-bay all appear to be electronic and neg earth which wont work on a pos earth system.

Positive earth system? Which modern rec/vc made for this you have installed ?

cheers Hans

Hi Hans, It came to me half converted with the rec, so I will take it off for a look see. I was wrong, Its neg earth ,looks like a podronics rec,I checked the alternator leads and they show no connection to earth and approx 5 ohms resistance to each other.The pod outputs appear to go directly to the battery with a pos wire going up to the HL.

Maybe a small relay on the output , energising its signal circuit?
Then when it gets a little current, the relay's switching action turns off the charge indicator.

Hi Bob,
Here's what I think, see if you agree...

Before you crank the engine, with ignition key turned to on,  and after you disconnect the maintenance charger, check the battery voltage. Then after your ride, check battery voltage when engine is turned off, with ignition key turned on. Compare results of system (battery) voltage from before and after your ride. If after your ride, the voltage is much lower than when you started, then your not charging the battery enough during the ride.

 Next, after disconnecting the maintenance charger, turn on ignition and measure voltage without engine running. Then crank engine, and check voltage at idle, and compare. Notice the difference in the way the headlamp looks where the engine is running at idle and not running with ignition on... you're probably not charging at idle, right? Rev the engine up to where the headlamp is brighter than it was with ignition on but engine not running, and thats where you are charging the battery. In essence you are using the headlamp as a charge indicator.

I also have noticed that - as I also use a maintenance charger until I ride, I get better results from my charging system with the largest amperage rated battery I can find and fit into the system. When fully charged, the higher capacity battery works as a better buffer towards the non charging rpms from the alternator. And since the alternator doesn't have to work as hard to recharge the higher capacity battery from minimal useage during idle, the system doesn't see the battery as a load, and can work to run the rest of the components(lights and coil, etc.)  I use two 5.1 amphour batteries in parallel, to make a 10.2 amphour, better buffering battery.
 
Bruce

One of these instruments (there might be others available) can give you precise informations about electric current to/from your battery, as well as it's voltage;
https://www.amazon.co.uk/DEOK-YB27VA-10A-DC0-100V-Digital-Voltmeter/dp/B00H0BTWHY/ref=sr_1_1?ie=UTF8&qid=1521328455&sr=8-1&keywords=dc+voltmeter+ammeter&refinements=p_89%3ADROK%7CDEOK
https://www.amazon.co.uk/Professional-Digital-3-5-30V-Ammeter-Voltage/dp/B0747SCT25/ref=sr_1_13?ie=UTF8&qid=1521328093&sr=8-13&keywords=dc+voltmeter+ammeter
https://www.amazon.co.uk/Voltmeter-Amme ... er+ammeter

Beware: the "shunt" or current measuring resistor has to be connected between battery -terminal and chassis/ground, for most of these instruments., so carefully read the installation instructions.

cheers Hans

My view is that a simple charge indicator lamp looks in keeping with an old motorbike.
Also, it gives useful information instantly - that the charging system is charging, with no interpretation needed.

Thanks Guys, I can imagine that there are others interested in this thread , so your imput is valued. My 250 is a bit non std with a couple of non functioning small indicator lights so replacing one of these with a small lamp is favourite .It will have to be simple as I am numbnuts with electrics.

Hi Jordan,
I absolutely agree, a simple indicator lamp will be much less distracting whild dodging the crazy drivers out there

Bruce

But, after all, what is "a simple indicator lamp", how/where you would connect it, and what would it finally indicate?

Hans