Battery draw

[Johnamino]

Morning all,

Having some battery issues on my 125cc

Does this look like an acceptable draw with the bike off?

Very new to all this!

Cheers

https://ibb.co/qr3j35Y

[Confusion]

[Johnamino]

Ah right! Cheers

Well, now it’s reading -0.10.....which I’m guessing is bad.

There’s nothing extra on the bike that would be drawing power. I recently changed the rear indicators. But with those completely disconnected, the draw is the same.

Any advice?

[Teflon-Mike]

What bike? What conditions?
If there's no non ignition switched accesories 'on' like an alarm or parking lights, There shouldn't be 'any' current draw when the engine is switched off.
With the ignition 'on'... current draw, should be negligible.... but you dont leave the bike with the ignition on, and the engine off for long periods, so shouldn't be an issue. Engine running.... amps aught be going 'in' to the battery, more often than they are coming out of it..... 'sept its a 125... so probably not.
So... what's the problem here that has you reaching for the multi-meter?
Most 125's have a self excited, or magneto type ignition, the electric for sparks made when the engine spins, so engine off, there aughtn't be any current draw to energise the coil; there should only be current sucked if accessories like an alarm or hard-wired headlamps are taking it.... hence what bike.
125's peculiarly DO 'seem' to suffer a lack of charge though; oft used by learners, they dont rag them too much; they rely heavily on the heavy amp-sucking e-start, and get used a lot for shorter town type runs, where a lot of engine ide time, sees the generator not making the amps that accessories and day-time running lamps suck; whilst short hops and many stalls see the e-start used heavily, and newer, especially car driving newbies, taught to use as tall a gear as possible, because of some nebulouse enviro-mental reasoning that it 'saves' fuel, sees the engine never spinning up the genny to make the ams it might to top up the battery, even when it could.... Chuck generally dire standards of maintenence on bikes in general, but 125's especially, and who actually bothers to check nattery electrolyte levels, and 125's batteries of go flat, and owners grumble thier bike wont start....
Usually not actually anything wrong with the bike... just its owners erroneous ideas....
Like I said... whats actually the problem that has you reaching for the widyometer, and what's the bike?
____________________
My Webby'Tef's-tQ, loads of stuff about my bikes, my Land-Rovers, and the stuff I do with them!
Current Bikes:'Honda VF1000F' ;'CB750F2N' ;'CB125TD ( 6 3 of em!)'; 'Montesa Cota 248'. Learner FAQ's:= 'U want to Ride a Motorbike! Where Do U start?'

[Johnamino]

It’s a Sinnis Trackstar (yes, don’t worry...I’ve heard all the groans already )

Basically, for the last few days the battery has been dead every morning. Even a battery that has been fully charged and left overnight will only just get things started by the morning. So I figure something is draining the battery when it’s idle and off. The voltmeter today would also suggest that. I’ve cleaned the Earth loom point. WD40’d all the switches, but still getting that reading from the voltmeter

Oh...it’s also a new battery. Because I thought that might be the issue at first

[Easy-X]

All you can do is grab a circuit diagram (pretty much any Chinese 125 diagram would probably do) and start disconnecting things until the drain goes away.

For the most part only the starter (and associated relay/solenoid) would be directly connected to the battery - everything else should connect via the fuses. Probably a bank of 3 or 4.

Monitor the drain, pull all the fuses. Hopefully one of them does something! Then trace that particular circuit till you come up with the culprit.
____________________
Royal Enfield Continental GT 535, Husqvarna Vitpilen 401, Yamaha XSR700, Honda Rebel, Yamaha DT175, Suzuki SV650 (loan) Fazer 600, Keeway Superlight 125, 50cc turd scooter

[Johnamino]

Fuses....yeah. I can’t find anything that looks like it might be a fuse hahah

[Easy-X]

They might not be immediately visible...

9 times out of 10 they'll be blade fuses in a bank but possibly covered - clip on plastic or rubber boot.

Otherwise you might have barrel fuses - usually a fat white or black sausage of plastic in-line in a cable.
____________________
Royal Enfield Continental GT 535, Husqvarna Vitpilen 401, Yamaha XSR700, Honda Rebel, Yamaha DT175, Suzuki SV650 (loan) Fazer 600, Keeway Superlight 125, 50cc turd scooter

[Confusion]

[Johnamino]

Apparently these things just have the one fuse off of the battery...

[Johnamino]

No accessories on it at all.

What does a regulator look like? 😆

[Easy-X]

Unlikely that's the only fuse...

Normally one would expect something like:

Battery > Main fuse (30A) > distribution board (various fuses)

But that's a generalisation of most motor vehicles TBH.

Yours may actually be scattered throughout the bike ofc - just to make life that much more interesting!
____________________
Royal Enfield Continental GT 535, Husqvarna Vitpilen 401, Yamaha XSR700, Honda Rebel, Yamaha DT175, Suzuki SV650 (loan) Fazer 600, Keeway Superlight 125, 50cc turd scooter

[Easy-X]

Regulator is usually a finned box about the size of a fag packet...

https://i.imgur.com/6pOU04L.jpg?1
____________________
Royal Enfield Continental GT 535, Husqvarna Vitpilen 401, Yamaha XSR700, Honda Rebel, Yamaha DT175, Suzuki SV650 (loan) Fazer 600, Keeway Superlight 125, 50cc turd scooter

[Johnamino]

OK....disconnected the regulator completely and there’s no drain.

This could be progress of sorts.

[Evil Hans]

[Confusion]

[Johnamino]

[Teflon-Mike]

Electric comes from coils in the stator of the generator, when a magnet wizzes past and gets the electrons exited.

On this kind of bike there's normally two or three windings on the stator to make electric to charge the battery, and a separate one to make volts to make sparks.

The electric comes out the windings on the stator, and into the regulator/rectifier.

The volts coming out the two or three generator windings are AC or alternating current; you get +ve volts when the magnet on the rotor passes one end of the winding, then -ve volts when the rotor had turned 180 deg and the magnet passes the other end of the winding.

The reg/rect units job is to take two or three AC inputs from the stator, each out of phase by however many degrees they are about the back-plate to each other; turn the AC into DC by a clever arrangement of one-way valves, or in in electricks, Diodes, then condition that electric a bit, and even out the pulses from the AC input going up and down in voltage, and 'clip' the voltage at just over 12v so it dont blow the headlamp bulbs and stuff. Hence rectifier... turning AC to DC and Regulator, regulating the voltage to 12v.

That provides the line 'in' to the battery; when the engine running amps go to the +ve terminal of the battery, where the main feed to everything else comes from; so, the equipment takes its electric straight from the generator; but when the generator isn't making as many amps as equipment wants, it takes it from the battery, when generator making more amps than equipment sucks, excess charges the battery.

Now... you have some current draw, when the ignition switched off.

The ignition switch doesn't actually turn on and off the ignition, it usually simply short circuits the ignition coil, so it kills sparks.

It also doesn't always turn on or off the supply to equipment from the battery. Often the brake light is on a constant feed... so that would be the first thing I checked TBH.... a faulty brake lamp switch has been cause of many a flattery....

Next check would be you are actually turning the key switch to 'off' not 'park'. There's often two positions where the key will come out, the 'park' position being at the very end, and switching 'on' the side light and tail....

That would typically be about 15W of bulbs switched on; Watts is Volts times Amps... so Amps is Watts over volts, and 15/12 is near enough 1A.. 10x more than you say you see on the widgyometer... if you is reading it right.... so dont dismiss straight away.

If the key-switch is definitely in the 'off' position; then there aughtn't be anything able to draw from the battery.... which is where the suggestion that lost amps is going back the way they came, through the Reg/Rect and or the Generator stator.

NOW.... you say that a new Reg/Rect is cheap enough to diagnose by substition.... but hold your horses!

The generator is a bludy great big chunk of steel that wizzes around on the end of the crank-shaft, with magnets in it; The stator a plate with a few windings on it, in very close proximity to that wizing metal rotor....

It is not unheard of for windings to get damaged by 'stuff' wizzing around them... especially since the rotor is magnetic and attracts any and every bit of steel chit on the floor... if its ever taken off and plonked wherever is to hand!

Worth pulling the genny cover and having a look-see for signs of obvious damage in there, before spending any money....

Reg/Rects ARE notorious; the diodes are electronic devices, that dont much like higher voltages or power; so Reg/Recs tend to beg the more expensive high current components.... and manufacturers, especially chinky ones, WIL try and get away with the cheapest devices with the skantest margins for reliability they can get away with.... B-U-T..... they are a pretty 'inert' assembly, and whilst they do go 'pop' its often the symptom not the cause.... so check everything else out first, OR you could have your new reg/rect go pop the same way in short order.... and be blaming the reg/rec for all eternity....
____________________
My Webby'Tef's-tQ, loads of stuff about my bikes, my Land-Rovers, and the stuff I do with them!
Current Bikes:'Honda VF1000F' ;'CB750F2N' ;'CB125TD ( 6 3 of em!)'; 'Montesa Cota 248'. Learner FAQ's:= 'U want to Ride a Motorbike! Where Do U start?'

[Johnamino]

Thanks, that’s very helpful

I’ve got a new reg on the way already though, so I’ll see how it goes

[Islander]

[Johnamino]

New reg fitted. No more power suckage

Cheers everyone

[Easy-X]

Another win for BCF
____________________
Royal Enfield Continental GT 535, Husqvarna Vitpilen 401, Yamaha XSR700, Honda Rebel, Yamaha DT175, Suzuki SV650 (loan) Fazer 600, Keeway Superlight 125, 50cc turd scooter