I recently bought a 2003 RS50 with roughly 7,000 miles on it and it was working fine until out of nowhere BAM engine cut out while I was riding. So it turns out that there is no spark, I thought it was the plug so I tested the ignition system by putting a screw where the plug goes and held it close to the cylinder head and still no spark. So... I am not exactly sure how I can go about testing which part is the cause of my problem. Any advice would be greatly appreciated.