Slide needle height?

[NemisusDM]

Do all 4 slide needles need to be in the same position?

I have
#1 at -1 lean
#2 at -1 lean
#3 at 0 center
#4 at ?

[bikerphil]

They should be all the same, in most cases in pos. 3 (center). I've experimented with them in other positions and 3 always worked the best for me.

[TADracer]

Center position on all four has always worked best for me too. I have tinkered with other positions but always come back to the center. Raising or lowering the needle even one small notch can have a big influence on how fast the mains are opened up at mid-throttle positions.

[prometheus578]

"All the same...."

Unless you want only two cylinders doing most the work.

[NemisusDM]

Would this create a buzz at W.O.T and a loss of power at over 100 mph????

[Dennyz]

I get a buzz at wide open throttle every time, the motor runs smooth :-)

[prometheus578]

Would this create a buzz at W.O.T and a loss of power at over 100 mph????

Hard to say....
By buzz, do you mean vibration?
That's a possability.
With different/unequal needle settings, you'll have cylinders putting out different amounts of power.
Sort of like at idle.. when the carbs are badly out of synch... runs badly, poor power, vibrates, etc.

[NemisusDM]

I set all the needles to the same height (3) and man has that engine quieted down!
Acceleration MUCH smoother!!

Thanks Guys!

[thewiz]

"I saw the needle and the damage done"

according to Neil Young ... and I think I know what he was talkin' about, in a manner of speaking. Just today checked the slide needles on my set of carbs .... only number three carb had the needle set in the center position. Rest were one notch rich ..... motor idled and ran fine but petered out badly between 5 and 6K rpm and eventually fouled the some of the plugs ... been makin' me crazy. Now it wants to pull the bars outa' my hands ..... yup.... center's the spot alright.