I've always run the same plugs in my bikes NGK BR8 or BR9. This is also what I'm running in my 200sx. In the KTM manual it says you should use a resistor plug or you risk frying the cdi unit. I've always been told if yu don't have a radio you don't need resistor plugs. What's the real difference and what should I be using.
I hate to disagree without being positive, but I don't think these are resistor plugs.
As to what KTM recommends, I can't say for sure, but I do know that on my RFS motor they recommend some really fancy and expensive plug that no one carries. I checked around and it is the same basic plug as what the Japanese stuff uses. The only difference is the design of the electrode. The cheaper and much more available plug works perfectly well.
If you do a search there was a detailed thread about this subject a while back...bottom line: the "R" in the BR8 indicates it is a resistor plug. Yes some CDIs are negatively effected by using a non-resistor plug, some aren't. Just use the recommended "R" plug, there is no appreciable benefit to using non-resistor plugs in your case.