2002 Suzuki GSX 600 F runs good when starts but now it wont start

Take a test light or multimeter and check if
power is getting to the starter each
time you push your starter button.

If so, the solenoid or starter relay is okay.

If not, then find the relay, it is at
the end of the battery positive wire.
It may be under the side cover or
under the seat.

Use your test light again and
see if power is on both sides
of the relays larger terminals when
you push your button (key on of course).
You should hear the solenoid or relay
click. It connects the positive
battery terminal to the starter
to make it run.

If it doesn't click or pass the power through
then check if power gets to it's
smaller wire when you push the button.
If not, could be the button, or
possibly something like a
bad side stand switch or engine
stop switch.