Needle position

I just took the Amal Premier carbs off my 1974 Commando Roadster for cleaning and maintenance. The clip on the needle in the left carb was in the bottom notch of the three notches. Unfortunately, I must have dislodged the clip on the needle in the right carb during removal as the clip was not connected to the needle at all so I don’t know which notch it was in prior to removal.
The workshop manual specifies that the clip be in the top notch, John Healy recommends the clip be in the second notch and mine was in the bottom notch. My question is where should I place the clip on re-assembly?

Test, don't guess.
Start in the middle, road test.

A lot of people think that both needles should be in the same position but each carb is different and setting can be quite different from each carb, its all about tuning my friend, as Concours has said start at the middle and test ride and adjust as needed but of course after any pull down carbs have to be retuned.

WEM said:

The workshop manual specifies that the clip be in the top notch, John Healy recommends the clip be in the second notch

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The original setting stated in the manual was the top (weakest) clip position, however, the factory later issued Service Release N3/48, May '73 instructing dealers to raise the needles to the middle clip position.

If it's too rich, it'll blubber/smell/be pokey. Too lean, it'll pop & backfire, be down on power.

ashman said:

A lot of people think that both needles should be in the same position but each carb is different and setting can be quite different from each carb, its all about tuning my friend.

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Tune your friend any way you like, but moving the needle up or down a notch is a big adjustment. I don’t believe any twin cylinder engine would need the needles in its twin carburettors set at different clip positions.

Well my friend then you don't know Amal carbs might be different in cold England but in hot countries like Aussie land carb difference can be a lot difference to barmy England, both crab setting to each cylinder can be at odds to each other, I have owned my Norton for 46 years , do all my own turning and as I say each carb and cylinder are different in adjustments.
We live in a hot temps what's the hottest it get in your way in summer, your summer temps is our day time temps in our winter, so carb adjustments are so much different.

Triton Thrasher said:

Tune your friend any way you like, but moving the needle up or down a notch is a big adjustment. I don’t believe any twin cylinder engine would need the needles in its twin carburettors set at different clip positions.

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I have in my carb jet box a selection of washers sold for Mikunis that increase your options by creating a half step, or even a quarter step.

They are designed to be a half or quarter size of the needle groove separation. Pop one under the clip to raise the needle quarter/half a notch, or go to the higher notch with one under the clip to raise the needle a half/quarter. To my mind, this is closer to the likely left/right jetting differences you might encounter.

The approach works on the Amal needle too, and I have used them on a 500 single with a MkII, but the needle grooves are a different distance apart.

You can find that carb set up will benefit from different settings, this can be lower down or higher up and a different size main jet isn't that uncommon. I first came across it on a Norton twin with a 2 into 1 exhaust in the '70s.

It is just that most of us can't be arsed to tweak that final step, and probably can't tell much difference in performance if we do!

If you are going to run Amals, I'd leave them where the factory bulletin suggested for your model Norton (in the middle). If the clip was off on one side and you couldn't tell, I would think you'll be good with the clips staying in the middle groove.

I've been using needle shims for a long time. Dynojet and Factory provided needle shims in their jet kits for Japanese manufactured inline 4's. So I have a bunch of them. Shims are definitely a fine tuners tuning device. I like taking the final step, but it is a fiddly process. If the tune is already very close at a standard clip position it is nearly impossible to tell if a shim makes a big difference. Full clip position steps usually make a big difference when going the wrong way.

I have a 2 into 1 exhaust on my Norton, but the headers pipes are basically the identical length, and go into a long collector section, and eventually into an unbaffled megaphone with Supertrapp plates at the tip. Needles are in the same position, each with a shim. Makes a difference in the tune. I run on the hotter plug lean side and the shims give me just a touch more fuel steady state cruising while maintaining excellent throttle response everywhere else. Not Amals.

"I have in my carb jet box a selection of washers sold for Mikunis that increase your options by creating a half step, or even a quarter step."

I punched my own, in two thicknesses of aluminum.
For the CV's on my Connie at first.

concours said:

"I have in my carb jet box a selection of washers sold for Mikunis that increase your options by creating a half step, or even a quarter step."

I punched my own, in two thicknesses of aluminum.
For the CV's on my Connie at first.

Muratec USA | 27.5 Ton Machines With Servo-Electric Punch Drive System

The machines in our 27.5 ton series incorporate the servo-electric punch drive system, allowing you to maximize productivity.

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I cut mine out of thick paper.

Triton Thrasher said:

Tune your friend any way you like, but moving the needle up or down a notch is a big adjustment. I don’t believe any twin cylinder engine would need the needles in its twin carburettors set at different clip positions.

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Needles are normally in same position on both cylinders, when carbs are tuned as well as can be, check out wide open throttle plug readings, one cylinder might require a bigger main jet than the other, this is fine carb tuning.