1994 Suzuki LTF250R Quad, No fuel getting to spark plug.
 

G'Day all,
I bought a used Suzuki 1994 LTF250R & it wont start. It has compression & plenty of spark (I just put a brand new spark plug in it) & the fuel seems to pump out ok & the carby bowl seem to get fuel in it but no fuel comes out the carby into the motor. The spark plug remains dry.
I have pulled the carby bowl off & cleaned out a jet as it was blocked but it still doesnt make any difference. I even tried to put a small amount of fuel directly into the combustion chamber through the spark plug hole then put the plug back in & start it. the motor gave a couple of coughs like it wanted to start but still nothing more.
I know not much at all about bike motors (or any motor for that matter but I am trying to learn as I go, I hope)

Hopefully someone out there can help me or point me in the direction af an online manual or pics for bike and/or carby (i've been told the carby is a Mikuni BST31).

Plus there is a lever near the top of the head on the motor. What is this for & when is it used?

Regards
Dan