Hello All:
 New here and just getting back into enduros after 40 years and I picked up a 75 dt250  a couple months ago that runs great but has wiring issue that I have been working out by searching past posts and finding most everything I need but I think I might have the wrong kill switch for the bike. It has a red/white and a brown wire coming out of it.
 When I hook it up (red/white to black/white and brown to ground) it is backwards - get spark with it "off" and no spark when on "run".
 When I check continuity I have it in "run" and not in "off" so grounding out in "run"
I pulled switch apart and cleaned it but see no way to switch it around. 
 Also have a 73 ct3 coming that was just picked up in La. and will be here in a couple weeks so probably looking for more help once it gets here.
Thanks,
John
 

 
 

Sounds like the switch you have is for a "battery ignition" model...  wire colors confirm this.

Switch you need will be "open" when switch is "on" and will be "closed" connecting the black/white to ground when switch is off.  

Might be a way to re-label what you have...  probably no way to re-wire.  

Or just leave it and think of it as an "anti-theft device"  

Thanks Mark!
That is what I thought and either I am going to re-label it or I was thinking the same as a good anti-theft.
Thanks Again!
John