Went out to the garage this morning all ready to do a couple of hours riding on my newly acquired '05 450 EXC, engine wouldn't start. Stuck a new plug in the plug boot, no spark. Tried 2 more plugs, no spark. I pulled the seat and tank and checked all the wiring connections, checked the kill button (OK), pulled off the spark plug boot, checked for continuity, it's OK. I'm frustrated by now, button everything up. Hit the starter one last try, engine fires up immediately. ***?? Anyone else had this problem and can shed some light on what's going on?