Thinking it's the carb...

[redline6th]

I just picked up a 99 warrior with a bit of a mid life crisis going on. It seems to be deciding when it wants to fire and start. I've got good spark, compression is not the issue, and I just put a new carb kit in it but it still runs when it wants to. There's a plunger on the left side of the bowl that goes into up into where the throttle cable feeds to. It's got a spring but it doesn't seem to want to move freely. I don't know if that could be the issue but when we move it with a pair of pliers, it then starts and runs (although poorly). This sound familiar to anyone?

 

[Warrior1996]

Thats the accelerator pump. It should move freely, but you shouldn't have to move it to start the bike.

 

[redline6th]

I'm stumped then... I've been into my carb on my YFZ multiple times without trouble like this. I've got spark and compression, if I had fuel in there, one would assume it should fire. Short of the timing being way out of whack, I can't think of what it could be aside from the carb.