Hi
im getting a tad desperate now and so is my kids i have a chinese 110cc quad brand unknown was running perfect then nothing replaced stator/coil/rectifier/spark plug and even battery all to no avail problems is
1- when resting spark plug on cylinder head and cranking engine no spark
2- when holding spark plug away from cylinder head about the thickness of a two pence piece or slightly more o get a spark am i correct in thinking the spark plug is grounding when touching the cylinder head if so what is the cure please as im now out of ideas
thank you

 

I love how I got spark problems on my quad right after reading your post..

Thankfully my spark plug was just filthy..

 

I'd agree that the plug seems to be grounding out.
I'm sure I'd try another plug.
I wonder if the ground from frame to engine could be bad.

 

Out of all the parts you listed that you replaced i see nothing about a CDI.. Thats usually the first thing that is replaced. Had the same issue and it turned out to be the cdi was bad.. got new ones off ebay 2 for $20.
Have you pulled the kill switch pin out of the cdi to eliminate a bad kill switch?
The spark plug is suppose to ground when touching the frame or engine..

Also check for bad broken wiring. especially behind your ignition key. Hard one to find or look at when your having issues. i found a few broken wires on mine.

 

*Trouble Shooter Guide for NO-SPARK Chinese Engines