Hi
please can someone tel me how many positions I should have on the ignition 
I have off position plus 3 more
thanks

That sounds right for a Euro version, as the last "on" position will be for the front and rear park lights.

Only definitive way to tell is to look at the wiring section in a parts manual for your model and, shown on this page, will be a drawing of what wires connect to what in each switch position. I've used these drawings to circuit test switches after rebuilding them.

The attached part is on UK fleabay - part number starts 512 (ie Euro model) and there are the same switch positions as yours. Not necessarily the correct one for the UK, as mainland Europe models might differ ever so slightly (CMSNL suggests that there are four different variations of this switch but, unfortunately, they don't have any photos).

New Genuine Yamaha Ignition Switch 512825084100 | eBay

Thanks AGAIN!!!!!!

Someone posted a wiring diagram for the DT250 models with the extra "parking light" switch position.  It looked like it came from a Haynes manual?

Here's a link to the thread with several pictures of wiring diagrams

www.yamaha-enduros.com/index.php/forums/...th-4-positions#76757

I only have 3 wires out of stator
1 black 1 yellow 1 red and green

it says on the electrical drawing position 1 on ignition green and white for charging but i don't have a green and white
if i connect the green and red to position 1 and 2 can it over charge when lights are off
I know position 2 with lights on charge
but what about position 1 

Have you had the flywheel off, to see if there is any trace of a green wire having been present and subsequently removed?

I'd want others to confirm but, if a voltage regulator was in place (a retro fit on these bikes up to 1975 or 1976), then it might be ok to connect the green/red from the flywheel magneto to the green in the main harness/loom. You'd obviously have to fashion your own splice or pigtail for this.

I'm guessing that the G/W on the switch legend is a typo, and it should just be G.

Later twin shock US models with a regulator had a green wire with a red stripe coming out of stator. This is for battery charging with lights off or lights on.

(Our models had the headlight switch in a handlebar switch instead of in the key switch.)

Yellow is for headlight.

Black is to ignition coil.

If you have the green/red connecting to the white (white goes to rectifier) with key on position 1 (engine runs, no headlight) and key on position 2 (engine runs, headlight on) you should be fine.

If you don't have a regulator, adding one is a good idea.