help not starting!!

[blackfzr1000]

ok guys we have no idea what happened here. the bike only has 13k on it and its not kicking over. its a 94 fzr 600 we got and we cant get it to start, we check for spark and thats good we have a fuel tank hooked up to the fuel line so we got fuel there. and i just checked the fuel pump and its kicking out fuel. it wants to start and it almost starts but doesn't. what else can we look for???

[blackfzr1000]

we are going to do the compression test friday, since my dad and i are working on the bike together kind of like a project to learn more about motorcycle motors. I build cars as a hobbie but i am always scared to dig into a motor cycle for some reason.. but while my father and i worked on it. he noticed that the baffles where not in the muffler. the old owner took them out of the exhaust to give him more sound he said. so what we would like to know is will that mess up the motor badly running it like that? i found another motor to pick up just incase this one is toast. what do you guys think? and one more thing. we checked the motor for spark and we let go of the button for the starter and like 5 to 10 seconds later we had a LOUD pop come out the exhaust, i mean i was in the middle of putting the spark wire back on to the plug and POP scared the blank out of us! that leads me to think its a bent valve somewhere what do you think?

[cad600]

I would make sure you have the plugs on in the correct order first. Also test the coils for the correct output. I had a problem with coils before and would occasionally get a back fire. A compression test will help narrow things down if the coils are not the cause. Pull the carbs off when you do the test. That way you can feel for blow by at the valve and crank breather. However, if the engine really does have 13K miles on it I don't think it will be the valves unless the thing was just ragged all to hell. There is a copy of the service manual in the Wiki. There is a section about starting trouble shooting that I would look at. It goes through all of the starting system electrical items.