My 02 f4i seems like it bogs when in low rpm in first gear. It also seems vibrate more than usual. Any ideas what could be causing the problem?

 

Air filter, spark plugs?

 

Just changed the air filter a week ago or so, how could i test the plugs?

Bike has 17k miles. I dont think it had sparks changed ever, i owned it since it had 5k

 

try running seafoam through the tank... works wonders... shouldnt hurt anyway.
manual suggests spark check at 16k. get a wire gauge, pull them out with a sparkplug wrench (search the forum for pics etc), and check if they are within spec (as in manual), and if the sparking point is clean (dont scratch it). If not put in some plugs...