My brother's boys quad isn't even getting close to starting. I've told hime to make sure it's getting gas so he said he totally cleaned hes carb and it still wasn't starting then I said check his ground for his coil he did and said there was plenty of fire so then I said check your stator and make sure you haven't sheared a pin or anything and he said that it hadn't. any other reasons that it could not crank any input would be helpful

 

we think it's the electronic ignition now

 

What are the circumstances concerning the no start? Sitting along time? Ran hot, and shut off? Made noises?
Any way, check the easy stuff. Kill switch? Got gas to the float bowl? air filter plugged up? latest mods...
Pull the spark plug, and do the spark test, (ground it on the engine and spin it over), try a new spark plug, if the old one looks glazed.

 

he said it was being rode and it just shut off no noise or nothung

 

Engines need three things to run. Might as well check the easy , and most likely stuff first. Out of gas? check to see if theres gas in the float bowl. Could be a bad fuel valve or plugged filter, so check the float bowl. Open the drain on the bottom of the bowl and make sure it comes out.
Then check for spark, pull the plug, put the wire back on, hold the plug against the motor( to ground it) and crank it over. Should be spark, if not check for why, kill switch, key switch, bad plug.
The third thing is compression, its a long shot, but if you have gas to carb and have spark, and it still wont start...then it could be compression, Is it a two stroke or 4 stroke?

 

I agree with the above and add look close at the spark it needs to be bright blue not a dull yellow .
You might have a bad CDI also compression should be over 100 psi if not = bore~piston
One other thing have you tried starting it on starter fluid ? If it's not flooded and wet then the starting fluid should fire the engine . Unless you dont have a good spark .
Good luck

 

yeah we've done al of that I am thinking it's top end 2.
it's a 2stroke

 

did you try to pop start it

 

no he didn't try to roll it off

 

did you check and see if the gas line was being pinched by something? check the spark plugs, you know what i do, i take them out, see if their dirty, i clean them off with a wire brush, and check for gap, and dip the end that screws in to the motor in gasoline, if its two stroke, dip it in the 2 stroke gas, just the bottom tip, the gas gives it a extra whomp of power if you will