I'm by far no jetting expert....but, I'm not sure what year your quad is, but here's where I am at. I have an '07, stock was a 148 main, I added a slip on and a K&N Air filter and I'm at a 155 main now. I'm wondering if you are way on the lean side??? I'm not sure what effect the cam would have on the jetting, but I would start with pulling the plug. You said you got it to fire off once so it should be colored somehow.
Also, check your timing, make sure when you installed the new cam you didn't get it out of time causing intake/exhaust valve issues.
Sorry, not a whole lot of help here, but I would start with the cam action, that is what should have really made the change to the quad firing or not. Even if you are lean it should still kick off I would think.
Good luck.
Ragin' Redneck
'07 400EX
iShock 3500 +2 A-Arms (Just added!!!)
DG X2 Slip-on,
Moose CDI,
K&N Air Filter (With Cover)
Pro Armor Nerfs with Heel Guards
DG Racing Baja Dull Skid Plate
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