I have replace the coil, sparkplug,flywheel, cdi and stator and still I have a weak spark in quad. The only way I can get a spark is to pull the plug from the cylinder and ground it to the head. If I leave the plug in the head and hook up another plug to the coil wire and ground it, I can get no spark. I should mention that the parts I used for replacements were used but I believe to be in good condition. I have not replaced the impulse coil mounted just outside the flywheel. I have checked the wires for continuity of the wires and they have all proved intact. I have sprayed starting fluid in the cylinder to make sure the problem was not fuel related. The starting fluid made no difference. Anybody got any ideas? My mechanic took a look at it and said he did not know what was wrong with it.

 

Which specific honda are we talking about?

Most of them have have a replacable spark plug cap, which unscrews from the spark plug wire. Try to tighten it if its loose, and if its already snug....remove the cap from the wire, and hold that wire about 1/4 " from the motor and crank it over...still weak? Sometimes those caps have too much resistance, and then the spark gets weak.

Are the impulse coil and the flywheels magnets, clean and shiney? no rust or corrosion?

 

take apart your ignition switch (they will come apart but be carefull)
good chance of green gung inside