Impossible to answer, depends on what model KTM you have.
NGK Spark Plug BR8ECM
bad plug bad plug cap stator
I have a 07 KTM 525 XCW and the manual call for 6mm on plug gap.
Got this off of KTM talk, 44HP for a 450 exc.
br10ecmix
0.60mm
NGK BR8ECM
No, 93-97 ktm 250-360 exc will fit it, not much else. found out the hard way on my 96 ktm 360exc
ask at a ktm shop
We use the nkg br9eix
NGK BR8HS with a .032" (0.8mm) gap