yeah, you are better off learning how to DIY,
that way if you have any problems you can sort it yourself when out riding etc.
Adjusting the screw made it idle a lot higher also
which way made the idle higher ?
here's a basic how to set mixtures-
start the bike up and let it run for a minute or so,
turn the idle speed screw (centre screw w/spring) inwards to raise the idle speed a bit, up to somewhere 1800 rpm, not too high
now the mixture screw can be adjusted.
turn the screw out a quarter of a turn.
listen to the engine carefully,
if the rpms drop, then the mixture screw needs to be turned back in 1/4 of a turn.
the rpms should increase to what they were,
now try tuning the mixture screw in another 1/4 of a turn
if the rpms increase again, then try another 1/4 of a turn in.
if at any stage the rpms drop, or it starts running funny, then turn the mixture screw back out a 1/4 of a turn
adjust the mixture screw, until the engine is revving at it's highest/smoothest point
when you are happy it is close to perfect, then you can unscrew the idle speed screw (with the big spring) until the rpms drop back down to a decent idle speed.
look at the orientation of the slot/head of the mixture screw,
turn it back in, and do it up until it bottoms out.
take note of how many turns out it was set at. eg 1.75 turns out
(this can also tell you if you need to swap the Pilot Jet for one bigger or smaller)
now reset the screw back to where it was again, like the example above, 1.75 turns out
now take the bike for a quick test run and note any changes.
the mixture screw can still be tweeked from there too, just go 1/8 - 1/16 turn at a time though.
you probably want to do a Spark Plug chop reading too if you can
this will show you how close your Main Jetting is,
fit a Brand New Spark Plug
then find a decent long stretch, with a slight incline to load it up a little.
get the bike into top gear and hold it pinned for 10 seconds,
then let the throttle go, turn it off, and pull the bike up.
now remove the plug and check out the colour of the Insulator and Tip inside the Spark plug.
eg Black sooty plug = Main jet too big, White plug = Main too small
you want a tan-ish tinge to it, for it to be running sweet.
see how it runs like that, and post up your results
