So i bought a hi bird off a guy the other day adjusted all the valves started up just fine, put it on my truck to get it home, unloaded it from the truck I had hooked it up to my car to jump it and it started up for 3 seconds killed and wouldn't start up since then, I put a new plug in it and still nothing.

 

check for spark, even with a new plug, check it while cranking the engine. do you know how to do that? take the plug out, put the coil wire on the plug, hold the rubber insulated boot end and ground the plug to the side of the engine or air fins, crank the starter. do you see spark? by the way, if you hold it in the wrong spot, it'll shock the **** out of you! so be careful.

on the other hand, when you hauled your quad in your pick up, did you isolate the petcock valve for travel? the quad could've been flooded badly. check your crankcase for gasoline contamination. if there's gasoline in it, change the oil.