Hello guys be great if someone helps me fix my problem I just recently bought a Dt125r with a problem with the headlight and back light not working thought would be easy but can't figure out what's wrong I've studied a wiring diagram and have noticed the headlight runs from the stator? But my stator seems fine as bike starts etc without battery connected . The loom that is kn the bike is a 3rm I was just wondering if this is the right loom or do I need a 3bn? If it is right any ideas to figure out what's wrong?

Yamaha's use different coils in the stator, your ignition system is completely and totally separate to the lighting and such.

You need to check you voltage at the battery for starters.

What should my battery be reading if it's charging?

Between 13.5 and 14.5ish volts at the terminals. At about 2 thousand rpm it should stabilise at the upper limit. If it just sits there and never gets above 11/12 volts then it's not charging.

Ok I'll have a look at this when I'm with my bike can anyone confirm whether a 3bn loom would work same as the 3rm ?

Ok update I ordered a new loom put it on and still the same battery sits at 12v when started no increase when I put the reader direct on the stator wires I get -0.34 so must be knackred if reading a minus voltage ? Guessing best thing to do is send it away to get rewound

Sound like it could be the stator but considering the sheer numbers of dt125s in the world i would consider good second hand. Stator failure is not common.

Ok thank you will have to see if I can find one 

Search the forum. There is a member that does electricals like this.

Speedshop (i think) 

Ok I've put a new stator on headlights work fine but the battery still sits at 12.5 v when running could the regulator be the problem thanks again for the help 

Just so we're clear here ok, did you measure across the Pos and Neg terminals of the battery to get this number? Just asking cos some folks measure at various places and it really helps if we're running on the same page here. As I said it should read about 13.5 to 14.5ish and rise as you rev it if not then DON'T concentrate on just one thing look for broken or loose wires first, it's usually a stupid fault rather than the most expensive.

Yes read from the positive and negative on the battery  like I said I first bought a new loom still the same then I bought a stator which now the headlights and rear light works old stator was fried but still getting no charge to the battery only thing I can thing of it being is the regulator/rectifier. 

Yep afraid that is your next port of call, you've replaced most everything else that might cause it. That's a bugger.