Starting problems (more like not starting problems)

[slevins20]

99 cbr600 carb'd.

cranks but wont turn over. occasional spitting popping and backfiring, but wont seem to turn over. just replaced the fuel line. fuel is clean.
im thinking that its not getting fuel...

fuel filter clogged?
dirty carb?
clogged injectors or w/e is on a carb'd motor?

i dont think its the plugs, but im not 100% sure. i havnt taken them out to look if they're making a spark or not. im actually going to buy the bike of my friends uncle and hes doing all the work on it.

someone help pleaseeeeee

[CORSCO]

When in doubt, replace your plugs! Has it sat for any amount of time? If it has sat for more than six months, you need a carb clean. Drain the carbs first. F4 is carb'ed the F4i is injected.

[slevins20]

yeah, i think the guy im buying it from is gona put new plugs in. wat about plug wires though? im not sure how long its been sitting, but im going to clean the carb(s) one way or another, whether thats the problem or not. i just want to get the thing running right now so i can ride it.

[CORSCO]

Motorcycles are not like cars where you replace plug wires everytime you do plugs. Only when they need to be replaced.