> You seem to be doing things pretty-well right. However once you have
> balanced the air-flow simply adjusting the jets for mixture balance
> shouldn't cause the air-flow balance to change, unless perhaps the pistons
> are rubbing on the covers or the needles not centralised in the jets. If
> adjusting the mixture after that makes the idle change so much that the
> engine is racing, then simply adjust both idle screws by the same amount
in
> the same direction to bring it back down again, otherwise don't bother
> trying to keep the idle revs at a particular speed whilst you are setting
> the mixture. The only other time you should have to check the air-balance
> again is when tightening the clamps, to make sure that the balance is the
> same off-idle as at idle. Don't forget the objective is to lift the
> *pistons* 1/32", the lifting pin itself will go up quite a way before it
> reaches the bottom of the piston and starts lifting it. In my experience
> HIFs are harder to judge than HSs, so be glad you have the latter.
> Whichever, by progressively weakening and richening the mixture, and
trying
> the lifting pins, you should be able to 'tune your ear' to detect the
> difference between weak and rich, at least, and by positioning the mixture
> mid-way between just being able to detect both should be about right.
After
> tweaking the mixture on one carb you have to go back and recheck the other
> as they are interdependent, making progressively smaller changes to each
> until they both do the same thing. All this should be after any problems
> with valve clearances, plugs, points gap, timing etc have been sorted of
> course.
>
> PaulH.
>
> ----- Original Message -----
> > Then, I started turning the jets flat by flat until I got the fastest
> > running speed with an even fire and exhaust sound. This necessitated
> > adjusting the idle speed and re-checking the airflow with the balancing
> > tool. The airflow was never the same with either carb at that point.
> >
> > At that point, the directions say to push up on the piston lifting pin
> > first on the front carb and then on the second. If the speed rises, the
> > carb is too rich, if the engine tries to stall, it's too lean, and if it
> > briefly goes up and comes back down, it's just right.
> >
> > What if I get none of the above? Well, sometimes it's obvious that it's
> > trying to stall. But otherwise, I might get the slightest quick blip
> > upwards, and then an attempt to stall. A few times have brought no
> > change at all.
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