wont start!

EDIT: The only way the quad will fire is if i pull off the carb, spary starting fluid in the intake and leave the carb off and kick it over. if i spray with the carb on the bike will not fire for some reason. Also, is there any way to see if gas IS getting into the cylinder... if the quad backfires every once in a while while trying to start it then that means that gas is present, correct?

just bought a 450 off my buddy and he said that it needs reshimmed and maybe timmed again. I brought the bike back home, pulled the valve cover off and checked it out, the timing is right on, but i cant find my feeler guage. I put everything back on and tried starting it for 20 mins. and i got nothing. The quad is getting spark because if i spray starter fluid it starts for a second. and its also getting gas because it backfires sometimes when im kicking it. I cleaned the carb etc. and im at a loss. Even though the valves may need to be shimmed the quad should still fire up right????? Also, what size deepwell socket do you need to get the spark plug out? i dont have anything to get the plug out with. ANY HELP WOULD BE APPERCIATED!!! thanks, josh

tryed starting it choked?

how old is the gas in the tank ?

if it has been sitting for a couple months I would get fresh fuel

Valves need to be adjusted.

valves need adjusted. My buddy's crf250r dirtbike wouldnt start not too long ago and i told him that we need to adjust his valves. I took is valve cover off and checked his intake valves and the right side had no clearance at all. This is what is happening in your case i'd say.
:macho

i found my feeler gauge and i measured the exhaust valves and they are right on, i will check the intake valves when i get home tonight.....

I put in brand new gas, and yes i did you the choke. thanks

guarentee one of the intake valves has no clearance or very little.

well i measured the intakes and i cant even fit the smallest feeler gauge size between which is .003! now, this quad has never had shim adjustments, i dont have a micrometer so i cant measure the shim, do you guys have any ball park estimate of what size the shims could be out of the factory. i know each bike is probably different, but about what size? AND also what size shims i should begin with to get me close to where i need to be? thanks a lot for your help!