Hi, recently fitted a Rex’s 12 volt conversion & ignition to my DT 250 C USA model, bike runs great the problem is the battery is not charging, I have read on various posts that this is a simple fix,just swap a couple of wires (Rex’s uk loom not compatible with my USA model) my problem is I can’t find on the forum which wires,can someone please point me in the right direction or tell me which wires to swap .I would contact Rex’s but been a holiday weekend hope someone here can help, 

Rex systems are hit and miss... as is their tech support... there are a lot of posts because of that.

This one has a post about how to rewire the plug. Just note that if this is the problem, your battery will be charging with lights on or lights off... just not both. If not charging at all, you have a different problem.

yamaha-enduros.com/index.php/forums/1977...volt-charging#148717

I fitted one of Rex's kits to my DT400, on one of the connectors I had to move one of the connections to another position in the plug.
The reason for this was that when you plugged it into the original loom, one of the wires was not connecting to the wire in the loom so a simple case of re locating the connector in the plug.
Cant remember which one it was, but if you take a look it will be obvious - if that is your problem.
Sorry cant be more helpful.
Apart from that it has been perfect.

Thanks for the info, when I had a better look at it you’re quite right,it was pretty obvious,green from new rectifier needs to go to white in loom , all charging, all lights on , great stuff , thanks again, one more question I bought this as a non runner so not really sure , only the kill switch stops the motor, not when I turn off with the key, is this correct or am I in the wiring again today 

Engine should turn off with the key, or kill switch it does on mine with the Rex's conversion.

In Rex's defence, when I called the Tech department about re locating the wire, they did say that there are variations in the looms even with same models of the same year, and said that you often have to make a small tweak when installing their system.

One other thing, mine was overcharging when I fitted the conversion, I followed their instruction and fitted an additional earth lead from the rectifier to the engine - no more overcharging.

Once you get it sorted I am sure you will be very pleased with the results.

Hi Andy - when you get some spare time, I would be grateful if you could describe the effects of the overcharging with the Rex conversion  and exactly what you had to wire from where to where. It may be very useful for future reference…. Thanks…