2006 gz turns but won't start.

[Water Warrior 2]

A bit strange. I wonder if the ignition system is weak and tends to fail when the starter is drawing power. You have proven the bike runs with a push start so everything else seems to be in order. Valves not closing sounds like some one is grasping at straws. I would be looking at E-bay for a replacement on the cheap.

[blaine]

If the valves get too tight,it will cause the condition you describe.When the valves are out of spec you don't have enough compression for the bike to start on it's own.But will start on a push,because the engine is spinning faster.Not saying this is your problem.But the first sign of valves too tight & needing adjustment,is hard/no starting cold.Valves usually get tighter with use, not looser.As the valve & valve seat wear,the distance between valve stem & adjuster decreases.
:cool:

[BonChaton]

Before I took it in, I checked the valve adjustment several times.
I even tried making them slightly loose to make sure the adjustment wasn't the problem.
I have a feeling that the person that owned the bike before me just rode it for a long time and never adjusted / maintained anything.
The valves may be burned and poorly seated and not closing fully.
I had to get it rolling at a pretty good rate to get it to start before I took it in.
It may run with bad valves, just at a loss of horse power.