I have a Chinese ATV, Baja 150 with a National Motor in it. I cannot find a spark plug that will fit? VIN starts with RKK and by the shifter the numbers are NM637232. No one knows what spark plug fits in this thing. My kid took out the old one and lost it. Any help please!!!

 

Information from Baja's website seems to indicate a GY6 engine, these are unusual as they don't have cooling fins, but the 4 stroke engine has a fan on the crankshaft, to blow air across it. If it is this type, the plug is Torch A7RTC

 

Thanks for the reply. It's not a GY6 engine and that seems to be the problem. This engine has fins like a traditional ATV motor. I have been to parts stores and searched the internet and no one knows what plug goes in that engine.

 

Put a couple of pictures up of both sides of the engine. Four strokes are almost always either a GY6 or a Honda clone, but the makers do mix and match a bit, using Honda 175cc or 200cc engines sleeved down or 125s bored and stroked, to give 150cc

 

Engine Number NM637232

 

I don't know small Honda models well enough to tell but it looks a lot like one. If it is a pushrod engine it almost certainly will be, as Honda went off overhead cams for their commuter bikes as they found the cam journals wore fast if owners didn't change the oil regularly. Loncin also copy Hondas and their CG150 is pretty close, but has the starter motor behind the cylinder. Can Baja themselves not help, they must have sold the machine originally?