Alright, so I just got my ex a few weeks ago. I'm not sure whether or not something is wrong. When I start it up, it sputters a little, then ticks, and cuts off. After it warms up, it's fine. But I just don't know what to think about the engine ticking like it does.

 

the 400ex motor is hardheaded when they are cold. Me and my dad have the same problems. The ticking is the cam lobes hitting the rocker arms. Me and my dads do the same thing. Just choke and pump the throtle like 2 times or so when it's cold.

 

Honda jets lean, to meet emissions requirements. If you are going to leave it stock, bump the jetting up a little. If you are going to make any mods (air intake, miffler, etc.), just live with it until you are ready to do those.

I have mine perfectly jetted, and it will start without the choke no matter how cold it is. It has a pumper carb, and all I do is press the throtle a couple of times to prime it, then it comes to life no problem.