dicky start solenoid

[macca k5]

hi
i seem to have a sticky starting solenoid so im either giving it a technical tap or kick starting the bike at the moment. i have pulled it apart as best as i can [ but it is mostly a sealed unit although the contacts cleaned up ok] any other ideas or should i just source a new one
?
cheers
Derek

[AGS]

my starter seems once in a while to run on after the engine starts - is this the sympton you are trying to correct?

[macca k5]

no i press the starter and all i get is a hum from the starting soleniod untill i give it a tap and then away it goes.