New kid in Nortown

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NKN said:
But I do have the left-hand panel secured by a Dzus fastener... but in the top left of the panel.

Yes, as one would expect for a Mk2, but not a Mk2A.

2A
New kid in Nortown


New kid in Nortown
 
NKN said:
Carbs also have some mysteries for me. Numbers on the body looks different: R35 vs L36

932 R35 (right hand) and L36 (left hand) would be the correct carbs for a Mk2.



NKN said:
And the sliders are playing the same game: 3 vs 4

Perhaps it's the reason why only one header is blue?

THE 'MB' numbers are just casting/foundry numbers and can be ignored.

Both slides are 3 1/2.
 
L.A.B. said:
Yes, as one would expect for a Mk2, but not a Mk2A.


OK, always good to know, thanks.


Most of you have their own tricks for cables' lubrification, let me talk about my favourite mixture. Some graphite powder + some petrol + some good grease. Put all this together, mix it and, after doing a little scotch funnel at the beginning of the cable, fend yourself to put some inside, pulling and pushing the cable. Don't need a lot but should be done slowly in 1 or 2 days.

New kid in Nortown


Petrol is the vehicule for the graphite powder and will bring it threw the cable and the grease is there against humidity. Won't even hurt some teflon hose inside and it would last for around 5 years. Your clutch lever will fell nice and smooth after that treatment.
 
L.A.B. said:
NKN said:
Carbs also have some mysteries for me. Numbers on the body looks different: R35 vs L36

932 R35 (right hand) and L36 (left hand) would be the correct carbs for a Mk2.



NKN said:
And the sliders are playing the same game: 3 vs 4

Perhaps it's the reason why only one header is blue?

THE 'MB' numbers are just casting/foundry numbers and can be ignored.

Both slides are 3 1/2.


Next time we'll meet, you would deserve a fresh beer :wink:
 
One smart thing on those Amals is that the two jets are on the same axle, almost one behind the other. Or am I wrong?

Never saw that before on any carb, Dell's, Bing's, Mikuni's, SU, Weber's...
 
NKN said:
Next time we'll meet, you would deserve a fresh beer :wink:

Thanks, but I never touch the stuff these days. :)


NKN said:
One smart thing on those Amals is that the two jets are on the same axle, almost one behind the other. Or am I wrong?

Sorry, I don't understand what you mean by "two jets are on the same axle"?
 
NKN said:
One smart thing on those Amals is that the two jets are on the same axle, almost one behind the other. Or am I wrong?

Never saw that before on any carb, Dell's, Bing's, Mikuni's, SU, Weber's...


The angled screw is just a throttle stop/adjuster. The horizontal one controls the pilot circuit.
 
NKN said:
Carbs also have some mysteries for me. Numbers on the body looks different: R35 vs L36

Yours is only the second carb I've seen stamped with the "X"'ed out numbers, then re-stamped.

The 74 John Player / MkIIA that I'm restoring is similar...

New kid in Nortown


New kid in Nortown
 
L.A.B. said:
NKN said:
Next time we'll meet, you would deserve a fresh beer :wink:

Thanks, but I never touch the stuff these days. :)


OK, what would you like instead?

NKN said:
One smart thing on those Amals is that the two jets are on the same axle, almost one behind the other. Or am I wrong?


Sorry, I don't understand what you mean by "two jets are on the same axle"?


Well, it looks like it's really time for me to change my glasses :roll:


New kid in Nortown



It's the main jet, and I don't know how you call it (where the blue arrow points) perhaps a diffuser?

New kid in Nortown


Is there an idle jet on Amals'? Or is it "built in" somewhere?
 
Danno said:
NKN said:
One smart thing on those Amals is that the two jets are on the same axle, almost one behind the other. Or am I wrong?

Never saw that before on any carb, Dell's, Bing's, Mikuni's, SU, Weber's...


The angled screw is just a throttle stop/adjuster. The horizontal one controls the pilot circuit.


Yes of course, thanks
 
grandpaul said:
NKN said:
Carbs also have some mysteries for me. Numbers on the body looks different: R35 vs L36

Yours is only the second carb I've seen stamped with the "X"'ed out numbers, then re-stamped.

The 74 John Player / MkIIA that I'm restoring is similar...

New kid in Nortown


New kid in Nortown


Since I'm reading this website, learning a lot from it and trying to improve my english, of course I've seen a lot of your posts, and I knew that we had something in common :lol:

Do you have an answer to that stange thing? Friday's carbs?
 
NKN said:
L.A.B. said:
NKN said:
Next time we'll meet, you would deserve a fresh beer :wink:

Thanks, but I never touch the stuff these days. :)


OK, what would you like instead?

Just a coffee, thanks. :)


NKN said:
Well, it looks like it's really time for me to change my glasses :roll:
It's the main jet, and I don't know how you call it (where the blue arrow points) perhaps a diffuser?

New kid in Nortown

That's the needle jet.

http://amalcarb.co.uk/rebuilding-mark-1 ... arburetter
http://amalcarb.co.uk/mk-i-concentric-s ... eries.html


NKN said:
Is there an idle jet on Amals'? Or is it "built in" somewhere?

The idle jet is a pressed-in brass bush opposite the pilot air screw in most 4-stroke Mk1 Concentrics (RH image).

New kid in Nortown



Mk1 Concentrics for 2-strokes generally have screw-in pilot jets.
New kid in Nortown
 
Hi NKN

The main jet and needle jet are indeed on the same axis or, to use another word, "concentric".
The needle jet, in conjunction with the tapered needle in the throttle slide, provides a gradual increase in fuel to match the increased airflow as the throttle is opened.
Once the throttle opening goes beyond are certain point, the needle jet becomes fully open. This jet,when fully open, is much bigger than the main jet, so the fuel supply is then controlled by the main jet.

The pilot or idle jet is, as you suggest, " built in" on these carbs. It is located behind a blanking plug on the opposite side of the carb to the air adjustment screw.
I did a modification on mine, as suggested in "Bushman's carb tuning secrets", by drilling out the plug, tapping a thread in the hole, and blanking it off with a shortened air screw.
This provides better access to the pilot jet for checking and cleaning. Older Amals had removable pilot jets screwed into the bottom of the carb body.
 
Sorry, I don't understand what you mean by "two jets are on the same axle"?

AXIS - thats why theyre ' Concentrics ' ! :shock:

Hava look & see if the mufflers are straight thru ' glass pac ' , so it breathes freeley .
 
Curious to know what you paid for your Norton? And, my two cents worth. I noticed that one of the header pipes was either new (the chrome was intact with no colour) and the other header pipe was a dark blue. The dark blue header pipe could be the result of: too rich a mixture, the bike left at idle too long before riding, an exhaust leak, etc.

Anyway, good luck with your purchase. I think you'll find that you will need not only the Norton manual but the two Norton Parts List and Manual. Some Whitworth tools and some Norton specialty tools at some point.

Good luck!

Bryan
 
Matt Spencer said:
Hava look & see if the mufflers are straight thru ' glass pac ' , so it breathes freeley .

Thanks for the input, makes me happy to discover that they are straight thru ones, as there is almost 62" length.

New kid in Nortown
 
cNwRestomod said:
Curious to know what you paid for your Norton? And, my two cents worth. I noticed that one of the header pipes was either new (the chrome was intact with no colour) and the other header pipe was a dark blue. The dark blue header pipe could be the result of: too rich a mixture, the bike left at idle too long before riding, an exhaust leak, etc.

Anyway, good luck with your purchase. I think you'll find that you will need not only the Norton manual but the two Norton Parts List and Manual. Some Whitworth tools and some Norton specialty tools at some point.

Good luck!

Bryan

The price was right given the amount of invoices provided. I tought that the blue header pipe was perhaps the result of a too lean mixture :?: (increase heat, no?) or a glogged carb, or a bad plug, or, as you wrote, something else...

With the bike I inherited the Haynes book and also the Chilton's one. Parts list was founded on AN, and following other advices as well, I will go for new carbs at Andover Norton (is a good place to buy them?) I already have some Whitworth wrenches because I helped a friend with his MG, and will get Norton specialty tools too. Which ones do you recommend to begin working on the bike?

Thanks!
 
MFB said:
Hi NKN

The main jet and needle jet are indeed on the same axis or, to use another word, "concentric".
The needle jet, in conjunction with the tapered needle in the throttle slide, provides a gradual increase in fuel to match the increased airflow as the throttle is opened.
Once the throttle opening goes beyond are certain point, the needle jet becomes fully open. This jet,when fully open, is much bigger than the main jet, so the fuel supply is then controlled by the main jet.

The pilot or idle jet is, as you suggest, " built in" on these carbs. It is located behind a blanking plug on the opposite side of the carb to the air adjustment screw.
I did a modification on mine, as suggested in "Bushman's carb tuning secrets", by drilling out the plug, tapping a thread in the hole, and blanking it off with a shortened air screw.
This provides better access to the pilot jet for checking and cleaning. Older Amals had removable pilot jets screwed into the bottom of the carb body.


Hi MFB,

Thanks for the carburetor lesson :wink: and the "Bushman's carb tuning secrets" very interesting learnings.
 
Decided to get some new Amal carbs, which ones will fit this bike? Should they be with the cutaway spray tubes for example? And long needles? What is the good reference for those with no need to be filled before mounting? With 260 main jets or 220? 106 needle jet and 31/2 sliders?

I do have the metal airbox filter and see thru peashooters.
 
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