Probably the switch for the lights as the tail light runs off the battery and the headlight runs of the yellow and black wire from engine, take switch apart and squirt some electrical contact cleaner on the parts or WD40.

@notgotaclue You can download the service manual for free from here; https://www.manualslib.com/manual/1203458/Yamaha-Dt125re-2005.html And well worth the money is a Haynes manual; https://www.ebay.co.uk/itm/Haynes-Workshop-Manual-Yamaha-TZR125-DT125R-DT125X-1987-2007-New-Service-Repair/254113315280?hash=item3b2a5579d0:g:Lu4AAOSw5LZcXG04:rk:31&frcectupt=true Both have lots of tips and troubleshooting guides!!!

can some one with a dtr confirm the fuse is 15 amp? a photo would be be helpful too

Yeah definitely should be a plug in there. 1 or 2 cables for the starter solenoid (to spin the starter) and then 1 or 2 for power to the rest of the bike

It's only on the RE do mains come on with engine off, but only after you start the engine.

Yep, did that, and all the other stuff as mentioned above

Sussed it, dead short in the generator on the yellow and red to ground

@Bluestoesonnose Wise call - A stock bulb would ensure that you can track down any problems you have, without changing anything else or maybe adding anymore to the mix for-sure. :thumbs_up_medium-light_skin_tone:

@col29 Electrics are always a PITA for-sure. Just be methodical and follow the wires back looking for cut's, fault's and rusted grounds etc.

@Bluestoesonnose WOW - that's insane, thanks tho.

Hi, can't post pictures as I'm missing it and they are almost £60 to replace

@Irongamer727 Strip it all down, give it all a damn good clean and de-rust, then re-install it ensuring a good grounding occurs. Once installed apply a blob of Vaseline to the ground points to prevent further rusting - works a treat and lasts a long time too!!!

@finnerz89 Ah, cheers

Been using Colin at the following: https://kojaycat.co.uk Very helpful and seems to have all the DTR125R electrical connector blocks in stock. Cheers

@Calum Cheers, just saved me finding out the hard way

Many thanks, I have found a company who can rewire it, I'm just waiting for a ball park cost. Cheers