hi all,its been awhile for me but this is the first problem ive had.all i did was replace the spark plugs(with the same style,brand and number) and a k&n air filter. now the bike wont start,it cranks over but sounds like it has no compression.i took the tank back off and made sure i hooked everything back up and as far as i can see i did. what the world could i have done ? any help would be great,thank you

 

Hey Maniac,

Have you rechecked all your connections? Make you you put the coils back on and plugged them back in. If it is cranking over, then it must not be a safety keeping it from firing. Is the fuel pump priming when you switch the ignition to on? Check the basics bud, get a little more info and come on back!

Best,
Antonio

 

Make sure your coil wires are replaced in the correct firing order.

 

sorry folks.1 thing i forgot to say when i was telling you all my problem was that i drained the cooling system to change the coolant,does this system have a sensor that will keep it from starting when there is no coolant in it ? sorry again,i know it would be helpful to know everything from the start

 

I have no idea about a coolant sensor. I do know that you can check your compression with a compression meter plugged into one of the spark plug holes.
The book lists my f3's correct compression at 179-183 psi.
Trial and error.
You should also check to see if you have spark. You can do this by taking just one of the coil wires off and placing a plug into it then grounding the tip to a piece of the frame or bare metal with the key on turn the starter over once or twice while grounding the plug and you should see a bit of spark. You can also do this in order to determine if one or more of your coil wires might be bad.