Amal carbs or Boyer ignition

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mean gene

mean gene

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Bin playing with my 750 street tracker. Installed belt drive, Madass's carb gantry and new 932 Amal carbs listed for 850"s. Belt drive was a snap and the carbs took some time to get tuned. Ended with a #2 needle in the bottom notch (richest position). Runs better then ever and goes down the road great. But doesn't want to come back down to Idle unless you drag the clutch when stopped. After it lowers to 1100 it idles very nicely. Have adjusted idle circuit that it increases then 1/2 turn out, (richer). I have heard Boyer's do weird things if low voltage but I have had it on a battery tender. Any ideas or experiences would be appreciated.
 
Turning the mixture screw out on an Amal is weakening the mixture. Turn in to richen. Opposite of how most carbs work. Start with 1 and 1/2 turns out. Shouldn't take more than a quater turn either way.
 
OOPS! thanks Started at 1 1/2 turns But when I turn them in Idle speed increases as thought your leaning it out not blubbering like rich?!!?!?!? Senior moment! I'll try tomorrow probably explains why it's hard to start also
 
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mean gene said:
OOPS! thanks Started at 1 1/2 turns But when I turn them in Idle speed increases as thought your leaning it out not blubbering like rich?!!?!?!? Senior moment! I'll try tomorrow probably explains why it's hard to start also
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All that means is that you’re richening it up to be ‘correct’. Keep winding it in more and it will start to hunt / 8 stroke.

How many turns out (from fully home) does it want to be to tick over nicely?

If it’s less than one full turn then your pilot jet is either too small, or partially blocked.

In my own experience, you want the tick over mixture a tad richer than ideal, to allow for the opening of the slide when accelerating.
 
When I said the belt drive was a snap, I meant it was easy to install. Size 17 pilot won't get a chance to play with it today.
 
If your needle clips are in the bottom notches, you need the next size in needle jets. If the clips are in the centre notches, you get the full range of adjustment. You might do better by using needles wit a slower taper. The slow running jets and slide cutaway only work for the first one-third of throttle opening. If the clips are in the centre position, you should be able to get the motor to cough by lowering them one notch. But do not ride the bike, if you are still getting the cough, raise the needles one. When the motor is cold, you should need choke.
 
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