cant begin to explain what a decent tune is worth, twiddling the screws wont get you very close at all to what the optimum would be
there is a place at the top of carlton gore rd, that road from the back of newmarket cinema's, up towards the hospital next to the domain. i cant remember what they're called, and to be honest ive never used them, but they caught my eye a couple of times, i'd reccomened going in there and having a chat to them, if they cant tune it themselves i'd put money on them telling you of a decent place to go