250-LR8B
NGK spark plugs have been around for a long time, they are an original fitment brand you can trust. These not a lot to say about plugs unless you want boring copy and paste technical details, a new one will work that's the main thing. If you are having engine issues always start with the easier (and usually cheapest) fix it solution which will be a new plug. The Spark plug LR8B is for KTM 50 and 65SX models, it has a 10mm thread and 16mm hex drive.
