Amal needles

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I've just had my 932 concentrics returned from being rebored and sleeved. At the same time I thought it would be a good idea to replace the needles and jets and whilst the jets are standard for an 850, i.e. main 260, needle 106 it would appear the needles are not. They have two identifying rings scored on top instead of the standard (I am told) 928/104 four ring scoring.

My question is should I replace them with standard needles, and therefore do I have to to replace the spray tubes as well ?, or should I just replace like with like as I did not have any problems before (apart from erratic idle due to slide wear)

Alan
 
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Off the net

SPRAY TUBES AND SLIDE NEEDLE VARIATIONS
The following notes from an Amal manual were contributed by Steve Shiver:
...grooves referred to are at the top of the needle, above the clip grooves
2 groved needle = PN 622/124 = 4 stroke
...used w 622/124 needle jet and 622/124 jet holder [600 series]
3 groved needle = 2 storke use w 622/079 jet, 622/080 jet holder
4 groved needle = 928/104, 4 stroke developed for 850 Nortons.
...used with stepped spray tube 928/107
Spray tubes
622/074 = 4 stroke, Cut Straight across
622/075 - 2 stroke, Cut at slight angle from oppostite side
622/123 = Trident, Cut at angle from mid point
928/107 = Norton MKIII special, stepped.


So you need the 4 ringed needle with the stepped spray tube (which if you have the right one in now just leave it there as it does not wear)
 

MichaelB

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Kommando is right on on this. The spray tube doesn't wear, but the needle and jet do.
I would match a new needle to the spray tube and replace the jet.
 
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Thanks guys, I reckon I have the 622/074 spray tubes which would match with the 2 groove needles currently fitted.

Not sure how to get the spray tubes out (special tool?) so will probably stick with what I've got, albeit with new needles, as the bike ran OK mid-range etc - unless of course someone knows better....


kommando said:
SPRAY TUBES AND SLIDE NEEDLE VARIATIONS...
2 groved needle = PN 622/124 = 4 stroke
...used w 622/124 needle jet and 622/124 jet holder [600 series]
4 groved needle = 928/104, 4 stroke developed for 850 Nortons.
...used with stepped spray tube 928/107
Spray tubes
622/074 = 4 stroke, Cut Straight across
928/107 = Norton MKIII special, stepped.

So you need the 4 ringed needle with the stepped spray tube (which if you have the right one in now just leave it there as it does not wear)
 
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The stepped tubes are important, without the stepped tubes the 260 mains are too small due to the Norton airflow, youwould need say 320 mains, the stepped tubes were the fix to steadily increasing main jet sizes.
 
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OK, but the question remains - how do I remove/fit the spray tube, do I need special tools :?:
 
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Alan
I just did the float levels on my carbs and used the heat method to adjust the needle seat height and float level. Remove anything combustible (as well as any unleaded left in there!) and sit the carb over a gas flame for 10-15 secs. A soft drift will tap the tube out from the venturi side. use the same method to install.
 
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