mixture screw By beakeyozz (Read 667 times)

[beakeyozz]

well here goes the idle mixture screw lve read up on this and some people say for a 150cc turn it out 3/4 of a turn others say 2 2 1/2 turns clockwise so what do you guys think lve set it at 3/4 turn scoot does 110klms about 70mph she doesnt bog down under load lve got 13 gram weights on her thx for your help

[alleyoop]

It all depends on the size of the PILOT JET, the bigger the pilot jet the less turns out the smaller the pilot jet the more turns out. The carb may be modded has a bigger pilot jet or the carb is bigger than the scoot came with stock, or if used someone up-jetted the carb or you live in a hot climate.

The 2 - 2 1/2 turns is JUST a starting point for a problem child that does not want to start or stay idling. After the motor starts then you adjust the Mixture Screw to get the highest IDLE on the Center stand after the motor warms up.

The 2 - 21/2 turns out is also a good setting that way if you live in part of a country that has extreme temperature changes from hot to cold you have plenty of adjustment in either direction
to make up for the air density change.

Take your case 3/4 out, if it happens to be running good at that setting BUT it is very cold in your area right now when and if the temp in your are rises above 70 degrees or higher you may not have enough adjustment to compensate for the air density.

What you have to worry is running LEAN at WOT for long stretches that will destroy a motor sooner rather than later.
Ride Safe
Alleyoop

[beakeyozz]

thx alley l go n have a play with her she does crackle n pop when l back off is that a sign of her running lean

[alleyoop]

Yes it is running LEAN if it crackles and pops when letting off the throttle. If it pops on throttle then it is RICH.
Alleyoop

[beakeyozz]

thxx got that now l go and apply thxxx