My bike runs sometimes but often will not start , when I press the ignition button a buzzing noise comes out o the headlight and bike will not start, other days it runs fine 1984 100 r

It could be the link from the starter button to the ignition coil. If you can check this for a current it should give an indication of the problem.

You have any aftermarket acc. ?

Checj your contacts on your statrer switch

sounds like the fuel pump my freind its just under the fuel tank on the fzr,s near the back of the tank sounds like replacement pump will sort it hope his helps

First check battery. then see that all the terminals ( battery, coils, and safe starter are corrosion free ).

batterty is dead check voltage!

I had the same problem with my 07 cbr but i found out that it wasn't the starter relay, the battery was just dead and i tried to recharge it but it was still dead, so it needed replaced with a new one. once this was done the bike started fine and the buzzing had stopped, so you should give that a go!

Check the ignition switch.  The headlight power runs through the ignition switch, and this turns off the headlight when the starter is engaged, which provides full battery power to the starter without the load from the headlight.  If there is damage to the starter button, it may be shorting out and causing the problem.

I'm having starting problems with my MOTO 6.5 ther is a 'buzzing' noise when the start button is pressed(the bike will not start or even try to fire) is it the solenoid? The buzzing noise is coming from the small item near the battery is this the solenoid? The battery is almost new so i know this isn't the problem. can anyone help? Sounds like a problem with the starter motor. Are you sure that the motor/piston is actually moved by the starter motor? If notthe buzzing noise is from the starter motor itself that runs 'free' without engaging the magnet that connects with the motor. The magnets can get 'sticky' and sometimes helped with a Careful hammering onto the starter motor. In any event you will need to rebuild or replace the starter motor unit. This all assumes that the moto still starts whenyou push her in second gear, right? Hope this helps and good luck. ,,,